Chapter Three: Experimental Experimental Chapter Three Experimental 3.1 Experimental This Chapter contains all the general procedures of all the chemical syntheses, Mizoroki-Heck reaction and Suzuki-Miyaura reaction 1 General Procedures Unless otherwise stated, all manipulations were performed under normal laboratory conditions All solvents and chemicals reagents were used as received Benzothiazole was purchased from Sigma-Aldrich Chemical Company and distilled prior to use Pd(OAc)2, triphenylphosphine, tricyclohexylphosphine, 2- diphenylphosphanylpyridine, pyrazine, trans-1,2-bis(4-pyridyl)ethylene, 1,2- bis(4pyridyl)ethane, 4,4’-bypyridine, 2-iodo-propane, 2-aminopyridine, 3-iodopyridine, 4tert-butyl-pyridine, imidazole, benzimidazole, benzooxazole, AgO2CCF3, Ag2O, Ag2CO3, AgOAc, KOBut and 2-phenylpyridine were purchased from Sigma-Aldrich and used as received 1,3-Dibenzylbenzimidazolium bromide284 and [Pt(C^N)(acac)]285 were prepared according to the literature H, 13C{1H}, 31P{1H}, 195 Pt{1H} and 19F{1H} NMR spectra were recorded on Bruker ACF 300 and Bruker AMX500 spectrometers using Me4Si (internal), 85% H3PO4 (31P) (external), 1.2 M K2PtCl4 in D2O (195Pt -1620 ppm) (external) and CF3CO2H (19F) (external) as standards respectively ESI and FAB mass spectra were obtained using a Finnigan LCQ The yields of C-C coupling products were 160 Synthesis, Structure and Catalytic Application of Novel Carbene Complexes with Benzothiazolin-2-ylidene Ligands Chapter Three: Experimental Experimental determined by using a Finnigan/MAT 95XL-T spectrometer Elemental analyses were performed on a Perkin-Elmer PE 2400 elemental analyzer at the Department of Chemistry, National University of Singapore For X-ray diffraction studies, suitable crystals were mounted on quartz fibers and X-ray data collected on a Bruker AXS APEX diffractometer, equipped with a CCD detector, using graphite-monochromated MoKα radiation (λ = 0.71073 Å) The data collection, indexing and lattice parameter determination and polarization effects were performed with the SMART suite programs.286 The integration of intensity of reflections and scaling was performed by SAINT The empirical absorption correction was performed by SADABS.287 The space group determination, structure solution and least-squares refinements on |F|2 were carried out with the SHELXTL.288 The structures were solved by direct methods to locate the heavy atoms, followed by difference maps for the light non-hydrogen atoms Anisotropic thermal parameters were refined for the rest of the non-hydrogen atoms The hydrogen atoms were placed in their ideal positions The crystals of complexes 2.21, 2.22, 2.34(a) and 2.40 contain two independent molecules in the asymmetric unit of the cell The two terminal carbon atoms of the propyl substituents of both molecules of C are disordered into two positions of occupancy ratio 55/45 The hydrogen atoms of complex 2.6 were refined to their coordinates shown The three cyclohexyl rings of complex 2.10(a) have relatively high thermal parameters and one of them is disordered into two positions at a 50:50 ratio 161 Synthesis, Structure and Catalytic Application of Novel Carbene Complexes with Benzothiazolin-2-ylidene Ligands Chapter Three: Experimental Experimental 3.2 Synthesis of A-D and complexes 2.1-2.44 3.2.1 Synthesis of A-D (Chapter Two, Section 2.2) 3-Benzylbenzothiazolium bromide, A A mixture of benzothiazole (3.71 g, 27.50 mmol) and benzyl bromide (4.70 g, 27.50 mmol) was stirred at 60 °C overnight The off-white solid thus obtained was washed several times with Et2O Diffusion of Et2O into a concentrated CH2Cl2 solution yielded transparent crystals suitable for X-ray diffraction studies Yield: 8.34 g (27.23 mmol, 99%) 1H NMR (300 MHz, CDCl3): δ 12.27 (s, 1H, NCH), 8.30 (d, 3JHH = 8.0 Hz, 1H, Ar-H), 8.08 (d, 3JHH = 8.43 Hz, 1H, Ar-H), 7.76 (m, 2H, Ar-H), 7.53 (m, 2H, Ar-H), 7.34 (m, 3H, Ar-H), 6.42 (s, 2H, CH2) 13C{1H} NMR (75.5 MHz, CDCl3): δ 165.1 (NCH), 140.1, 131.5, 131.3, 130.0, 129.5, 129.4, 129.0, 128.3, 124.8, 117.2 (Ar-C), 56.7 (CH2) MS (ESI, positive mode) m/z (%): 226 (100) [M - Br]+ Anal Calc for C14H12BrNS (M = 306.22): C, 54.91; H, 3.95; N, 4.57; S, 10.47 Found: C, 54.72; H, 3.73; N, 4.48; S, 10.46 3-(2-Propenyl)benzothiazolium bromide, B Compound B was prepared using a similar procedure to A from benzothiazole (3.71 g, 27.50 mmol) and allyl bromide (3.33 g, 27.50 mmol) The solid thus obtained was washed several times with Et2O Diffusion of Et2O into a concentrated CH2Cl2 solution yielded transparent crystals suitable for X-ray diffraction studies Yield: 5.71 g (22.30 mmol, 81%) 1H NMR (300 MHz, CDCl3): δ 11.87 (s, 1H, NCH) (in D2O, this signal appears at 10.37 ppm),13 8.45 (d, 1H, 3JHH = 7.7 Hz, Ar–H), 8.14 (d, 1H, 162 Synthesis, Structure and Catalytic Application of Novel Carbene Complexes with Benzothiazolin-2-ylidene Ligands Chapter Three: Experimental Experimental JHH = 8.2 Hz, Ar–H), 7.82 (t, 1H, 3JHH = 7.8 Hz, Ar–H), 7.74 (t, 1H, 3JHH = 7.3 Hz, Ar–H), 6.14 (m, 1H, CH2CH=CH2), 5.83 (d, 2H, 3JHH = 6.1 Hz, CH2CHCH2), 5.55 (d, 1H, 3JHH = 17.1 Hz, CH2CH=CHHtrans), 5.46 (d, 1H, 3JHH = 10.4 Hz, CH2CH=CHHcis) C{1H} NMR (75.5 MHz, CDCl3): δ 165.0 (NCS), 140.1, 131.3 (Ar–C), 130.0 13 (CH2CH=CH2), 128.9, 128.8, 125.3, 123.0 (Ar–C), 117.1 (CH2CH=CH2), 55.4 (NCH2) MS (ESI, positive mode) m/z (%): 176 (100) [M − Br]+ Anal Calc for C10H10BrNS (M = 256.16): C, 46.89; H, 3.93; N, 5.47; S, 12.52 Found: C, 46.48; H, 3.47; N, 5.32; S, 12.46 3-Propylbenzothiazolium bromide, C Compound C was prepared in using a similar procedure to A from benzothiazole (3.71 g, 27.50 mmol) and 1-bromopropane (3.38 g, 27.50 mmol) at 120 °C The orange solid thus obtained was washed several times with Et2O The solid was continuously washed with ethyl acetate until a yellow solid was obtained Diffusion of Et2O into a concentrated CH2Cl2 solution yielded transparent crystals suitable for Xray diffraction studies Yield: 5.55 g (21.50 mmol, 78%) 1H NMR (500 MHz, CDCl3): δ 12.09 (s, 1H, NCH), 8.43 (d, 3JHH = 8.2 Hz, 1H, Ar–H), 8.11 (d, 3JHH = 8.9 Hz, 1H, Ar–H), 7.89 (t, 1H, Ar–H), 7.80 (t, 1H, Ar–H), 5.12 (t, 2H, 3JHH = 7.3 Hz, CH2CH2CH3), 2.17 (pseudo sext, 2H, CH2CH2CH3), 1.08 (t, 3H, Hz,CH2CH2CH3) JHH =7.3 C{1H} NMR (125MHz,CDCl3): δ 164.9 (NCH), 140.2, 131.4, 13 130.2, 129.1, 125.3, 116.5 (Ar–C), 54.7 (CH2CH2CH3), 22.9 (CH2CH2CH3), 0.9 (CH2CH2CH3) MS (ESI, positive mode) m/z (%): 178 (100) [M − Br]+ Anal Calc for C10H12BrNS (M = 258.18): C, 46.52; H, 4.68; N, 5.43; S, 12.42 Found: C, 46.18; H, 4.76; N, 5.51; S, 12.81 163 Synthesis, Structure and Catalytic Application of Novel Carbene Complexes with Benzothiazolin-2-ylidene Ligands Chapter Three: Experimental Experimental 3-Isopropylbenzothiazolium triiodide, D D was prepared similarly to A from benzothiazole (3.74 g, 27.65 mmol) and 2-iodopropane (15.33 g, 90.16 mmol) at 100 °C for days The brown oil thus obtained was washed several times with ethyl acetate to afford yellow solid Diffusion of Et2O into a concentrated CH2Cl2 solution yielded transparent crystals suitable for X-ray diffraction studies Yield: 4.91 g ( 8.78 mmol, 32%) 1H NMR (500 MHz, CDCl3): δ 11.52 (s, 1H, NCHS), 8.54 (d, 3JHH = 8.2 Hz, 1H, Ar-H), 8.24 (d, 3JHH = 8.8 Hz, 1H, Ar-H), 7.90 (t, 3JHH = 7.90Hz, 1H, Ar-H), 7.80 (t, 3JHH = 7.9 Hz, 1H, Ar-H), 5.51 (m, JHH = 6.6 Hz, 1H, CH(CH3)2), 1.93 (d, 3JHH = 6.9 Hz, 6H, CH(CH3)2) 13C{1H} NMR (125 MHz, CDCl3): δ 163.1 (s, NCHS), 140.1, 131.6, 130.3, 129.2, 125.8, 117.1 (s, Ar-C), 57.4 (s, CH(CH3)2), 23.6 (s, CH(CH3)2) MS (ESI, positive mode) m/z (%): 178 (100) [M - I3]+ Anal Calc for C10H12BrNS (M = 558.99): C, 21.49; H, 2.16; N, 2.51; S, 5.74 Found: C, 21.81; H, 2.16; N, 2.54; S, 5.12 3.2.2 Synthesis of Complexes 2.1-2.4 (Chapter Two, Section 2.3) cis-Dibromobis(3-benzylbenzothiazolin-2-ylidene)palladium(II), 2.1 A mixture of A (306 mg, mmol) and Pd(OAc)2 (112 mg, 0.5 mmol) was suspended in CH3CN (30 mL) and refluxed overnight The orange precipitate thus obtained was washed several times with Et2O and water Crystallization from CH2Cl2/Et2O gave yellow crystalline needles suitable for X-ray diffraction Yield: 326 mg (0.45 mmol, 91%) 1H NMR (500 MHz, DMSO-d6): δ 8.12 (d, 3JHH = 7.55 Hz, 2H, Ar-H), 7.537.25 (m, 16H, Ar-H), 6.38 (br s, 4H, CH2) 13C{1H} NMR (125 MHz, DMSO-d6): δ 203.8 (NCH), 142.5, 135.4, 134.6, 129.1, 128.9, 127.7, 127.4, 126.0, 123.2, 116.3 (Ar-C), 58.7 (CH2) MS (ESI, positive mode) m/z (%): 637 (100) [M - Br]+ Anal 164 Synthesis, Structure and Catalytic Application of Novel Carbene Complexes with Benzothiazolin-2-ylidene Ligands Chapter Three: Experimental Experimental Calc for C28H22Br2N2PdS2 (M = 716.84): C, 46.92; H, 3.09; N, 3.91; S, 8.94 Found: C, 45.75; H, 3.20; N, 3.97; S, 8.51 Repeated purification steps did not give satisfactory analytical data for 2.1 It was prone to solvate (and H2O) entrapment Dibromo(µ-dibromo)bis(3-benzylbenzothiazolin-2-ylidene)-dipalladium(II), 2.2(a) A mixture of A (306 mg, mmol) and Pd(OAc)2 (112 mg, 0.5 mmol) was suspended in DMSO (5 mL) and heated at 70 °C overnight The solvent was removed under vacuum, and CHCl3 (10 mL) was added The mixture was left to stand for days The orange solid thus obtained was filtered, washed with small amounts of CHCl3 and Et2O, and dried under vacuum X-ray-quality crystals were obtained from a saturated CHCl3 solution Yield: 109 mg (0.11 mmol, 45%) 1H NMR (300.1 MHz, DMSO-d6): δ 8.15 (br s, 2H, Ar-H), 7.70-7.29 (m, 16H, Ar-H), 6.50 (s, 4H, CH2) 13C{1H} NMR (75.5 MHz, DMSO-d6): δ 142.2, 136.0, 134.3, 129.1, 128.7, 128.0, 127.5, 125.9, 123.1, 115.8 (Ar-C), 58.9 (CH2) The signal for the carbene carbon could not be detected under the given conditions MS (FAB) m/z (%): 903 (100) [M - Br]+ Anal Calc for Pd2Br4(C14H9NS)2.CHCl3 (M = 1102.45): C, 31.59; H, 2.10; N, 2.54; S, 5.82 Found: C, 31.59; H, 2.32; N, 2.76; S, 6.09 trans-Dibromo(acetonitrile)(3-benzylbenzothiazolin-2-ylidene)palladium(II), 2.3 CH3CN (15 mL) was added to complex 2.2(a) (295 mg, 0.3 mmol) and the mixture heated under reflux overnight The clear yellow solution was cooled to ambient temperature and the solvent evaporated under vacuum Yellow cubic single crystals of were obtained from diffusion of Et2O into a concentrated CH3CN solution upon standing Yield: 295 mg (0.55 mmol, 92%) was obtained 1H NMR (300.1 MHz, CDCl3): δ 7.80 (m, 1H, Ar-H), 7.50-7.34 (m, 8H, Ar-H), 6.46 (br s, 2H, CH2), 2.00 (s, 165 Synthesis, Structure and Catalytic Application of Novel Carbene Complexes with Benzothiazolin-2-ylidene Ligands Chapter Three: Experimental Experimental 3H, CH3CN) 13C{1H} NMR (75.5 MHz, CDCl3): δ 191.5 (NCS), 142.2, 136.4, 133.0, 129.2, 129.1, 128.8, 127.4, 127.2, 125.6, 121.9 (Ar-C), 115.1 (CH3CN), 59.7 (CH2), 1.78 (CH3CN) MS (FAB) m/z (%): 572 (18) [M + K]+ Anal Calc for C16H14Br2N2PdS (M = 532.58): C, 36.08; H, 2.65; N, 5.26; S, 6.02 Found: C, 33.52; H, 3.00; N, 5.33; S, 6.16 Repeated purification steps did not give satisfactory analytical data for 2.3 It is susceptible to loss of the CH3CN ligand and subsequent dimerization to form 2.2(a).217 trans-Dibromo(3-benzylbenzothiazolin-2-ylidene)(N,Ndimethylformamide) palladium(II), 2.4 A solution of complex 2.2(a) (295 mg, 0.30 mmol) in DMF (15 mL) was heated at 80 °C overnight The yellow solution thus obtained was cooled to ambient temperature and filtered, and the solvent of the filtrate was removed under vacuum Diffusion of Et2O into a concentrated DMF solution afforded yellow cubic crystals of suitable for X-ray diffraction studies Yield: 288 mg (0.51 mmol, 85%) was obtained 1H NMR (300.1 MHz, CDCl3): δ 8.02 (s, 1H, CHO), 7.82 (d, 3JHH = 6.7 Hz, 2H, Ar-H), 7.52-7.30 (m, 7H, Ar-H), 6.51 (br s, 2H, CH2), 2.96 (s, 3H, CH3), 2.88 (s, 3H, CH3) C{1H} NMR (75.5 MHz, CDCl3): δ 191.9 (NCS), 162.6 (CHO), 142.5, 13 136.4, 133.0, 129.3, 128.8, 127.5, 127.2, 125.6, 121.9, 115.2 (Ar-C), 59.9 (CH2), 36.5 (CH3), 31.5 (CH3) MS (FAB) m/z (%): 412 (40) [M - Br - DMF]+ Anal Calc for C17H18Br2N2OPdS (M = 564.63): C, 36.16; H, 3.21; N, 4.96; S, 5.68 Found: C, 36.43; H, 3.25; N, 5.15; S, 5.83 166 Synthesis, Structure and Catalytic Application of Novel Carbene Complexes with Benzothiazolin-2-ylidene Ligands Chapter Three: Experimental Experimental 3.2.3 Synthesis of Complexes 2.5-2.8 (Chapter Two, Section 2.4) cis-Dibromobis[3-(2-propenyl)benzothiazolin-2-ylidene]palladium(II), cis-2.5 A mixture of B (256 mg, mmol) and Pd(OAc)2 (112 mg, 0.5 mmol) was suspended in CH3CN (30 ml) and refluxed overnight The white precipitate thus obtained was washed several times with Et2O and water Diffusion of Et2O into a DMF solution yielded crystals suitable for X-ray diffraction studies Yield: 99 mg (0.16 mmol, 32%) H NMR (500 MHz, DMSO-d6): δ 8.13 (d, 2H, 3JHH = 8.2 Hz, Ar–H), 7.95 (d, 2H, JHH = 8.2 Hz, Ar–H), 7.60 (t, 2H, 3JHH = 7.9 Hz, Ar–H), 7.52 (t, 2H, 3JHH = 7.6 Hz, Ar–H), 6.28 (m, 2H, CH2CHCH2), 5.92 (broad d, 3JHH = 4.4 Hz, 4H, CH2CHCH2), 5.41 (broad d, 2H, 3JHH = 17.0 Hz, CH2CH=CHHtrans), 5.36 (broad d, 2H, 3JHH = 10.1 Hz, CH2CH=CHHcis) C{1H}NMR(125 MHz, DMSO-d6): δ 203.0 (NCS), 142.7, 13 135.1 (Ar–C), 131.8 (CH2CH=CH2), 127.7, 126.1 (Ar–C), 123.2, 120.6 (Ar–C), 116.2 (CH2CH=CH2), 58.1 (NCH2) MS (ESI, positive mode) m/z (%): 537 (100) [M − Br]+ Anal Calc for C20H18Br2N2PdS2 (M = 616.73): C, 38.95; H, 2.94, N, 4.54; S, 10.40 Found: C, 38.49; H, 3.06; N, 4.45; S, 10.02 trans-Dibromobis[3-(2-propenyl)benzothiazolin-2-ylidene)palladium(II), trans- 2.5 Column chromatography on the filtrate of the above reaction (SiO2, ethyl acetate) afforded trans-2.5 as an orange powder Yield: 185 mg (0.30 mmol, 60%) 1H NMR (500 MHz, DMSO-d6): δ 8.17–8.11 (m, 2H, Ar–H), 8.01–7.94 (m, 2H, Ar–H), 7.63– 7.53 (m, 4H, Ar–H), 6.27 (m, 2H, CH2CHCH2), 5.92–5.85 (broad m, 4H, CH2CHCH2), 5.59 (d, 2H, 3JHH = 17.0 Hz, CH2CH=CHHtrans), 5.40 (d, 2H, 3JHH = 9.4 Hz, CH2CH=CHHcis) C{1H} NMR (125 MHz, DMSO-d6): δ 212.2 (NCS), 142.6, 13 167 Synthesis, Structure and Catalytic Application of Novel Carbene Complexes with Benzothiazolin-2-ylidene Ligands Chapter Three: Experimental Experimental 135.1 (Ar–C), 131.7 (CH2CH=CH2), 127.7, 126.1 (Ar–C), 123.4, 120.6 (Ar–C), 116.2 (CH2CH=CH2), 58.3 (NCH2) MS (ESI, positive ions): m/z (%) 537 (100) [M − Br]+ Anal Calc for C20H18Br2N2PdS2 (M = 616.73): C, 38.95; H, 2.94, N, 4.54; S, 10.40 Found: C, 37.85; H, 3.39; N, 3.78; S, 9.17 cis-Di(trifluoroacetato)bis[3-(2-propenyl)benzothiazolin-2-ylidene]palladium(II), 2.8 A mixture of complex cis-2.5 (308 mg, 0.5 mmol) and AgO2CCF3 (221 mg, mmol) was suspended in CH3CN (20 ml) and stirred at r.t overnight shielded from light The resulting light yellow suspension was filtered from the precipitated AgBr over Celite and the solvent removed in vacuum to give the crude product as a white powder It was washed several times with Et2O Yield: 157 mg (0.23 mmol, 46%) 1H NMR(500 MHz, DMSO-d6): δ 8.19 (d, 2H, 3JHH = 7.6 Hz, Ar–H), 8.00 (d, 2H, 3JHH = 8.2 Hz, Ar–H), 7.65 (t, 2H, 3JHH = 7.9 Hz, Ar–H), 7.57 (t, 2H, 3JHH = 7.6 Hz, Ar–H), 6.07 (m, 2H, CH2CH=CH2), 5.95 (d, 4H, 3JHH = 5.1 Hz, CH2CHCH2), 5.22 (d, 2H, 3JHH = 10.1 Hz, CH2CH=CHHcis), 5.16 (d, 2H, 3JHH = 17.6 Hz, CH2CH=CHHtrans) 13C{1H} NMR (125 MHz, DMSO-d6): δ 192.0 (NCS), 159.0 (COO), 142.5, 135.1 (Ar–C), 131.7 (CH2CH=CH2), 128.1, 126.5, 123.6, 119.7 (Ar–C), 116.5 (CH2CH=CH2), 57.7 (NCH2) The signals for the CF3 could not be detected under the given conditions 19 F{1H} NMR (282.38 MHz, DMSO-d6): δ 2.49 (s, CF3) MS (ESI, positive mode) m/z (%): 487 (64) [M − 2O2CCF3 + OCH3]+ Anal Calc for C24H18F6N2O4PdS2 (M = 682.95): C, 42.21; H, 2.66; N, 4.10; S, 9.39 Found: C, 41.80; H, 2.38; N, 4.15; S, 9.46 168 Synthesis, Structure and Catalytic Application of Novel Carbene Complexes with Benzothiazolin-2-ylidene Ligands Chapter Three: Experimental Experimental 3.2.4 Synthesis of Complexes 2.2(b) and 2.9-2.11 (Chapter Two, Section 2.5) Dibromo(µ-dibromo)bis(3-propylbenzothiazolin-2-ylidene)dipalladium(II), 2.2(b) Complex 2.2(b) was prepared similarly to 2.2(a) from C (518 mg, mmol) and Pd(OAc)2 (225 mg, mmol) Yield: 337 mg (0.38 mmol, 76%) 1H NMR (300 MHz, DMSO-d6): δ 8.13 (br, m, 4H, Ar–H), 7.59 (m, 4H, Ar–H), 5.07 (br, t, 4H, CH2CH2CH3), 2.17 (br, m, 4H, CH2CH2CH3), 1.08 (t, 6H, CH2CH2CH3) 13 JHH = 6.0 Hz, C{1H} NMR (75 MHz, DMSO-d6): δ 142.0, 135.2, 127.2, 125.4, 122.5, 114.8 (Ar–C), 54.8 (CH2CH2CH3), 21.4 (CH2CH2CH3), 11.07 (CH2CH2CH3) MS (FAB, positive ions) m/z (%): 807 (10) [M − Br]+ Anal Calc C20H22Br4N2Pd2S2 (M = 886.98): C, 27.08; H, 2.50; N, 3.16; S, 7.23 Found: C, 26.27; H, 2.90;N, 3.05; S, 7.89 cis-Dibromo(3-benzylbenzothiazolin-2-ylidene)(triphenylphosphine)Pd(II), 2.9(a) A mixture of 2.2(a) (983 mg, mmol) and PPh3 (525 mg, mmol) was suspended in CH2Cl2 (5 mL) and stirred overnight at r.t Et2O (15 mL) was added to give a yellow precipitate which was filtered and washed with Et2O Yield: 905 mg (1.20 mmol, 60%) 1H NMR (500 MHz, CDCl3): δ 7.71–7.70 (m, 1H, Ar–H), 7.63–7.59 (m, 7H, Ar–H) 7.54–7.52 (m, 1H, Ar–H), 7.49–7.47 (m, 1H, Ar–H), 7.37–7.34 (m, 4H, Ar– H), 7.31–7.28 (m, 1H, Ar–H), 7.25–7.22 (m, 8H, Ar–H), 7.16–7.15 (m, 1H, Ar–H), 6.53 (d, 1H, 2JHH = 15.1 Hz, NCHH), 5.00 (d, 1H, 2JHH = 15.1 Hz, NCHH) P{1H}NMR(202.43 MHz, CDCl3): δ 27.3 (s, PPh3) 31 13 C{1H} NMR(125 MHz, CDCl3): δ 208.4 (NCS), 167.8, 142.2, 136.5 (Ar–C), 134.5 (d, 2/3JCP = 10.90 Hz, Ar– C), 132.6, 132.5 (Ar–C), 131.1 (d, 4JCP = 2.74 Hz, Ar–C), 130.8, 130.0, 129.6, 128.9 169 Synthesis, Structure and Catalytic Application of Novel Carbene Complexes with Benzothiazolin-2-ylidene Ligands Chapter Three: Experimental Experimental 6.64 (d, 3JHH = 7.6 Hz, 1H, Ar-H), 6.47 (d, 2JHH = 15.3 Hz, 1H, CH2), 6.20 (d, 2JHH = 15.3 Hz, 1H, CH2).13C{1H} NMR (125 MHz, CDCl3): δ 197.5 (s, NSHC), 165.2, 150.9, 144.8, 143.9, 143.3, 138.9, 135.9, 134.3, 133.8, 130.6, 128.9, 128.2, 127.5, 126.7, 124.9, 123.9, 123.8, 122.6, 122.1, 119.2, 118.3, 115.2 (s, Ar-C), 59.5 (s, CH2) 195 Pt{1H} NMR (107 MHz, CDCl3): δ - 3578 MS (ESI, positive mode) m/z (%): 575 [M - Br]+ Anal Calc for C25H19BrN2PtS (M = 654.48): C, 45.88; H, 2.93; N, 4.28; S, 4.90 Found: C, 46.20; H, 3.08; N, 4.13; S, 4.72 [Pt(C^N)(N-propylbenzothiazolin-2-ylidene)(Br)] 2.39(b) Complex 2.39(b) was prepared as described above for 2.39(a) from 3propylbenzothiazolium bromide (0.08 g, 0.29 mmol) and Pt(C^N)(acac) (0.12 g, 0.26 mmol) Yellow single crystals of 2.39(b) were obtained from a diffusion of Et2O into a concentrated CH2Cl2 solution Yield: 0.06 g (0.099 mmol, 38%) 1H NMR (500 MHz, CDCl3): δ 9.80 (d, 3JHH = 5.7 Hz, JPtH = ca 22 Hz, 1H, Ar-H), 7.84 (d, 3JHH = 8.9 Hz, 2H, Ar-H), 7.75 (m, 1H, Ar-H), 7.69 (d, 3JHH = 8.2 Hz, 1H, Ar-H), 7.58-7.49 (m, 3H, Ar-H), 7.27 (t, 3JHH = 6.9 Hz, 1H, Ar-H), 7.10 (t, 3JHH = 8.2 Hz, 1H, Ar-H), 6.90 (t, 3JHH = 8.2 Hz, 1H, Ar-H), 6.45 (d, 3JHH = 7.6 Hz, 1H, Ar-H), 4.97 (m, 1H, CHHCH2CH3), 4.85 (m, 1H, CHHCH2CH3), 2.23 (m, 1H, CH2CHHCH3), 2.07 (m, 1H, CH2CHHCH3), 1.02 (t, CH2CH2CH3) 13 JHH = 7.3 Hz, 3H, C{1H} NMR (125 MHz, CDCl3): δ 195.3 (s, NSHC), 165.1, 150.8, 144.8, 143.9, 143.4, 138.9, 135.8, 134.3, 130.2, 128.9, 128.8, 126.7, 124.9, 123.8, 123.1, 118.3, 114.0 (s, Ar-C), 56.2 (s, CH2CH2CH3), 22.7 (s, CH2CH2CH3), 14.1 (s, CH2CH2CH3) 195 Pt{1H} NMR (107 MHz, CDCl3): δ - 3581 MS (ESI, positive mode) m/z (%): 527 [M - Br]+ Anal Calc for C21H19BrN2PtS.2Et2O (M = 194 Synthesis, Structure and Catalytic Application of Novel Carbene Complexes with Benzothiazolin-2-ylidene Ligands Chapter Three: Experimental Experimental 754.68): C, 46.15; H, 5.21; N, 3.71; S, 4.25 Found: C, 45.20; H, 4.16; N, 3.98; S, 2.70 [Pt(C^N)( N, N-dibenzylbenzimidazoly-2-ylidene)(Br)], 2.40 Complex 2.40 was prepared as described above as described above for 2.39(a) from dibenzylbenzimidazolium bromide (0.17 g, 0.44 mmol) and Pt(C^N)(acac) (0.16 g, 0.37 mmol) A 20 : mixture of isomers was observed in the 1H NMR spectrum Yellow single crystals of 2.40 were obtained from a diffusion of Et2O into a concentrated CH2Cl2 solution Yield: 0.15 g (0.20 mmol, 54%) 1H NMR of major isomer (300 MHz, CDCl3): δ 8.47 (d, 3JHH = 6.9 Hz, JPtH = 25 Hz , 1H, ArH), 7.70-7.62 (m, 2H, Ar-H), 7.51 (d, 3JHH = 7.4 Hz, 1H, Ar-H), 7.46-7.11 (m, 17H, Ar-H), 6.36 (t, 3JHH = 7.31 Hz, 1H, Ar-H), 6.14 (d, 2JHH = 15.3 Hz, 2H, CH2), 5.95 (d, 2JHH = 15.3 Hz, 2H, CH2) 13 C{1H} NMR (75 MHz, CDCl3): δ 193.7 (s, NHC), 169.2 (s, JPt-C = 34.9 Hz, Ar-H), 158.2 (s, Ar-C), 150.8 (s, JPt-C = 18.0 Hz, Ar-C), 145.9, 137.1, 135.7, 135.5, 134.9 (s, Ar-C), 130.5 (s, JPt-C = 16.4 Hz, ArC), 128.4, 127.9, 127.8, 123.8, 123.3, 123.0 (s, Ar-C), 121.9 (s, JPt-C = 22.4 Hz, Ar-C), 118.9 (s, JPt-C = 22.4 Hz, Ar-C), 111.5 (Ar-C), 51.7 (s, JPt-C = 8.73 Hz, CH2) 195 Pt{1H} NMR (107 MHz, CDCl3): δ - 3584 MS (ESI, positive mode) m/z (%): 648 [M - Br]+ Anal Calc for C32H26BrN3Pt.H2O (M = 745.57): C, 51.55; H, 3.79; N, 5.64 Found: C, 50.21; H, 3.97; N, 4.89 195 Synthesis, Structure and Catalytic Application of Novel Carbene Complexes with Benzothiazolin-2-ylidene Ligands Chapter Three: Experimental Experimental 3.3 General Procedure for C-C Coupling Reactions 3.3.1 General Procedure for the Mizoroki-Heck Reaction in Section 2.3 NaOAc (1.5 mmol), aryl halide (1 mmol), and tert-butyl acrylate (1.2 mmol) were placed in a reaction flask equipped with a stirring bar DMF (3 mL) was introduced, and the resulting suspension was heated to 100 °C for 10 before the catalyst was added After the desired reaction time, the reaction mixture was cooled to ambient temperature Water was added, and the aqueous phase was extracted with dichloromethane (3 x mL) The combined organic phases were dried over MgSO4 and filtered, and the solution was analyzed by GC/MS 3.3.2 General Procedure for the Suzuki-Miyaura Reaction in Section 2.4-2.6 and 2.9 Cs2CO3 (2 mmol), aryl halide (1 mmol) and phenylboronic acid (1.5 mmol) were placed in a reaction flask equipped with a stirring bar Solvent (5ml) was introduced and the resulting suspension was heated to 100 ◦C for 10 before the catalyst was added After the desired reaction times, the reaction mixture was allowed to cool to ambient temperature Water was added and the aqueous phase was extracted with CH2Cl2 (3 × 4ml) The combined organic phase was dried over MgSO4, filtered and the solution analyzed by GC-MS 196 Synthesis, Structure and Catalytic Application of Novel Carbene Complexes with Benzothiazolin-2-ylidene Ligands Chapter Three: Experimental Experimental 3.3.3 General Procedure for the sp3-sp2 and sp3-sp3 Coupling Reaction in Chapter two, Section 2.7 K2CO3 (1.2 mmol), benzyl halide (0.8 mmol) and phenylboronic acid (0.8 mmol) were placed in a reaction flask equipped with a stirring bar Solvent (5 mL) was introduced and the resulting suspension was heated to 60 °C for 10 or stirred at ambient temperature for 10 before the catalyst was added After the desired reaction times, the reaction mixture was allowed to cool to ambient temperature Water was added and the aqueous phase was extracted with CH2Cl2 (3 × mL) The combined organic phases were dried over MgSO4, filtered and the solution was analyzed by GC/MS 3.4 Synthesis of Compound 2.41-2.43 (Chapter Two, Section 2.12) The work in Section 2.12 was a collabration work with Cardiff University The general procedure is given below 3.4.1 General Procedure Unless otherwise stated, all manipulations were performed by using standard Schlenk techniques under argon or in a nitrogen glovebox Solvents were dried by standard methods Bis(1,5-cyclooctadiene)nickel(0),289 1-allyl-3-methylimidazolium bromide (2.41(a)),2901-butyl-3-allyl-imidazolium trimethylphenyl)-1H-imidazole,292 bromide (2.41(b)),291 1-(2,3,6- 1-(2,6-diisopropylphenyl)-1H-imidazole,292 3- allylthiazolium bromide (2.41(e)),293 3-(3-butenyl)-4-methylthiazolium bromide 197 Synthesis, Structure and Catalytic Application of Novel Carbene Complexes with Benzothiazolin-2-ylidene Ligands Chapter Three: Experimental Experimental (2.41k),294 1-(4-pentenyl)-3-methylimidazolium bromide (2.41q),295 1,3-bis-(2,4,6trimethylphenyl)-imidazol-2-ylidene (IMes), 1,3-bis(2,6-diisopropylphenyl)imidazol2-ylidene (IPr), 1,3-bis(2,6-diisopropylphenyl)-4,5-dimethylimidazol-2-ylidene (Me2IPr), and 1,3-bis(2,4,6-trimethylphenyl)imidazolidin-2-ylidene (SIMes)296 were prepared according to published procedures Benzothiazole was purchased from Alfa Aesar and distilled prior to use Other commercially available compounds were used without purification H and 13C NMR spectra were recorded at 293 K on Bruker DPX 400 or 500 spectrometers with chemical shifts (δ) referenced to internal solvent resonances and reported relative to Me4Si Coupling constants (J) are given in Hz, and NMR peaks are labelled as s = singlet, d = doublet, q = quartet, and m = multiplet Electrospray ionization mass spectrometry (ESI/MS) was performed on a Waters LCCT Premier XE instrument Elemental analyses were carried out by Warwick Analytical Service Ltd., Coventry, U.K X-ray diffraction data were obtained on a Kappa Nonius CCD diffractometer equipped with an Oxford cryogenic system to maintain the crystals at 150 K Structure solution and refinement were performed by Dr Andreas Stasch General Procedure A A mixture of N-substituted imidazole (1 mmol) and alkenyl halide (1.2 mmol) was stirred at 70 °C overnight The reaction mixture was cooled to room temperature, and the yellow oily product or white solid thus obtained washed several times with EtOAc and Et2O and dried under vacuum General Procedure B An oven-dried Schlenk tube was charged with the Narylimidazole (1 mmol) and alkenyl halide (1.2 mmol) THF (20 mL) was added, and the mixture was stirred at 70 °C overnight The solvent was removed under vacuum, 198 Synthesis, Structure and Catalytic Application of Novel Carbene Complexes with Benzothiazolin-2-ylidene Ligands Chapter Three: Experimental Experimental and Et2O (40 mL) was added The off-white solid thus obtained was washed several times with Et2O and dried under vacuum 3-Allyl-1-mesitylimidazolium Bromide, 2.41(c) General procedure B was followed using 1-(2,3,6-trimethylphenyl)-1H-imidazole (186 mg, mmol) and allyl bromide (121 mg, 1.2 mmol), giving a white solid Yield: 280 mg (0.91 mmol, 91%) 1H NMR (500.13 MHz, D2O): δ 10.46 (s, 1H, im C2-H), 7.71 (s, 1H, im C4/5-H), 7.54 (s, 1H, C4/5-H), 7.21 (s, 2H, Ar H), 6.19-6.05 (m, 1H, CH2CH=CH2), 5.47 (d, 1H, 3JHH = 10.0 Hz, CH2CH=CHHHcis), 5.40 (d, 1H, 3JHH = 15.0 Hz, CH2CH=CHHHtrans), 4.92 (d, 2H, 3JHH = 5.0 Hz, CH2CH=CH2), 2.31 (s, 3H, CH3), 2.00 (s, 6H, CH3) 13C{1H} NMR (125.03 MHz, D2O): δ 141.5 (im-C2), 134.7 (Ar-C), 130.8 (CH2CH=CH2), 130.2, 129.2, 124.1, 123.1 (Ar-C), 121.4 (CH2CH=CH2), 51.9 (CH2CH=CH2), 20.2 (CH3), 16.3 (CH3) Anal Calc for C15H19BrN2 (M = 307.23): C, 58.64; H, 6.23; N, 9.12 Found: C, 58.08; H, 6.21; N, 9.21 3-Allyl-1-(2,6-diisopropylphenyl)imidazolium Bromide, 2.41(d) General procedure B was followed using 1-(2,6-diisopropylphenyl)-1H-imidazole (227 mg, mmol) and allyl bromide (121 mg, 1.2 mmol), giving a off-white solid Yield: 201 mg (0.60 mmol, 60%) 1H NMR (500.13 MHz, D2O): δ 9.14 (s, 1H, im C2-H), 7.75 (s, im C4/5-H), 7.67 (s, im C4/5-H), 7.60 (t, 1H, 3JHH = 7.5 Hz, Ar-H), 7.43 (d, 2H, 3JHH = 5.0 Hz, Ar-H), 6.19-6.08 (m, 1H, CH2CH=CH2), 5.47 (d, 1H, 3JHH = 10.0 Hz, CH2CH=CHHHcis), 5.40 (d, 1H, 3JHH = 15.0 Hz, CH2CH=CHHHtrans), 4.93 (d, 2H, 3JHH = 10.0 Hz, CH2CH=CH2), 2.39-2.28 (m, 2H, CH(CH3)), 1.11 (d, 12H, JHH = 5.0 Hz, CH(CH3)2) 13 C{1H} NMR (125.03 MHz, D2O): δ 145.8 (im-C2), 199 Synthesis, Structure and Catalytic Application of Novel Carbene Complexes with Benzothiazolin-2-ylidene Ligands Chapter Three: Experimental Experimental 136.8 (Ar-C), 131.8 (CH2CH=CH2), 130.2, 125.4, 124.5, 123.3 (Ar-C), 121.4 (CH2CH=CH2), 51.9 (CH2CH=CH2), 28.3 (CH(CH3)), 23.3 (CH3) Anal Calc for C18H25BrN2: C, 61.89; H, 7.21; N, 8.02 Found: C, 61.61; H, 7.19; N, 7.84 This compound has been reported previously, but no analytical data were provided.297 1-Butenyl-3-methylimidazolium Bromide, 2.41(f) General procedure A was followed using 1-methylimidazole (82 mg, mmol) and 4bromo-1-butene (162 mg, 1.2 mmol), giving a yellow oil Yield: 162 mg (0.75 mmol, 75%) Characterization data were identical with those in the literature.298 1-Butyl-3-(3-butenyl)imidazolium Bromide, 2.41(g) General procedure A was followed using N-butylimidazole (124 mg, mmol) and 4bromo-1-butene (162 mg, 1.2 mmol), giving a yellow oil Yield: 181 mg (0.70 mmol, 70%) 1H NMR (500.13 MHz, D2O): δ 8.74 (s, 1H, im C2-H), 7.45 (d, 2H, 3JHH = 5.0 Hz, im C4/5-H), 5.79-5.73 (m, 1H, CH2CH2CH=CH2), 5.05 (d, 1H, 3JHH = 10.0 Hz, CH2CH2CH=CHHcis), 4.98 (d, 1H, 3JHH = 20.0 Hz, CH2CH2CH=CHHtrans), 4.24 (t, 2H, 3JHH = 5.0 Hz, CH2CH2CH=CH2), 4.15 (t, 2H, 3JHH = 7.5 Hz, CH2CH2CH2CH3), 2.57 (q, 2H, 3JHH = 6.7 Hz, CH2CH2CH=CH2), 1.80 (quent, 2H, 3JHH = 7.5 Hz, CH2CH2CH2CH3), 1.24 (sextet, 2H, 3JHH = 6.7 Hz, CH2CH2CH2CH3), 0.87 (t, 3H, JHH = 7.5 Hz, CH2CH2CH2CH3) C{1H} NMR (125.03 MHz, D2O): δ 135.2 (im- 13 C2), 133.3 (CH2CH2CH=CH2), 122.4 (im C4/5), 118.8 (CH2CH2CH=CH2), 49.3 (CH2CH2CH2CH3), 48.8 (CH2CH2CH=CH2), 33.8 (CH2CH2CH=CH2), 31.2 (CH2CH2CH2CH3), 18.7 (CH2CH2CH2CH3), 12.61 (CH3) MS (ESI, positive mode) m/z (%): 179.1541 (100) [M-Br]+ (calcd 179.1548, dev -3.9 ppm) This compound was found to be too hygroscopic for satisfactory elemental analysis 200 Synthesis, Structure and Catalytic Application of Novel Carbene Complexes with Benzothiazolin-2-ylidene Ligands Chapter Three: Experimental Experimental 1-Mesityl-3-(3-butenyl)imidazolium Bromide, 2.41(h) General procedure B was followed using 1-(2,3,6-trimethylphenyl)-1Himidazole (186 mg, mmol) and 4-bromo-1-butene (162 mg, 1.2 mmol), giving an off-white solid Yield: 138 mg (0.43 mmol, 43%) 1H NMR (500.13 MHz, D2O): δ 8.89 (s, 1H, im C2-H), 7.70 (s, 1H, im C4/5-H), 7.49 (s, 1H, im C4/5-H), 7.10 (s, 2H, Ar-H), 5.885.73 (m, 1H, CH2CH2CH=CH2), 5.08 (d, 1H, 3JHH = 10.0 Hz, CH2CH2CH=CHHcis), 5.01 (d, 1H, 3JHH = 20.0 Hz, CH2CH2CH=CHHtrans), 4.37 (t, 2H, 3JHH = 5.0 Hz, CH2CH2CH=CH2), 2.64 (q, 2H, 3JHH = 5.0 Hz, CH2CH2CH=CH2), 2.29 (s, 3H, CH3), 1.96 (s, 6H, CH3) 13C{1H} NMR (125.03 MHz, D2O): δ 141.5 (im-C2), 136.3, 135.3 (Ar-C), 133.1 (CH2CH2CH=CH2), 130.8, 129.2, 124.1, 123.0 (Ar-C), 119.4 (CH2CH2CH=CH2), 49.1 (CH2CH2CH=CH2), 33.9 (CH2CH2CH=CH2), 20.2 (CH3), 17.1 (CH3) MS (ESI, positive mode) m/z: 241.1706 (100) [M-Br]+ (calcd 241.1705, dev 0.4 ppm) Anal Calc for C16H21BrN2: C, 59.82; H, 6.59; N, 8.72 Found: C, 59.92; H, 6.59; N, 8.75 1-(2,6-Diisopropylphenyl)-3-(3-butenyl)imidazolium Bromide, 2.41(i) General procedure B was followed using 1-(2,6-diisopropylphenyl)-1H-imidazole (227 mg, mmol) and 4-bromo-1-butene (162 mg, 1.2 mmol), giving a off-white solid Yield: 94 mg (0.26 mmol, 26%) 1H NMR (500.13 MHz, D2O): δ 9.05 (s, 1H, im C2-H), 7.72 (s, 1H, im C4/5-H), 7.62 (s, 1H, im C4/5-H), 7.57 (t, 1H, 3JHH = 10.0 Hz, Ar-H), 7.40 (d, 1H, 3JHH = 10.0, Ar-H), 5.81-5.65 (m, 1H, CH2CH2CH=CH2), 5.09 (d, 1H, 3JHH = 10.0 Hz, CH2CH2CH=CHHcis), 5.01 (d, 1H, 3JHH = 15.0 Hz, CH2CH2CH=CHHtrans), 4.38 (t, 2H, 3JHH = 7.5 Hz, CH2CH2CH=CH2), 2.64 (q, 2H, 3JHH = 5.0 Hz, CH2CH2CH=CH2), 2.34-2.23 (m, 2H, CH(CH3)2), 1.09 (d, 12H, 3JHH = 5.0 Hz, CH(CH3)2) 13C{1H} NMR (125.03 MHz, D2O): δ 145.8 (im-C2), 136.7, 135.4 (Ar-C), 201 Synthesis, Structure and Catalytic Application of Novel Carbene Complexes with Benzothiazolin-2-ylidene Ligands Chapter Three: Experimental Experimental 133.0 (CH2CH2CH=CH2), 131.8, 130.3, 125.4, 124.5, 123.0 (Ar-C), 119.4 (CH2CH2CH=CH2), 49.1 (CH2CH2CH=CH2), 34.0 (CH2CH2CH=CH2), 28.3 (CH(CH3)2), 23.4 (CH(CH3)2) Anal Calc for C19H27BrN2: C, 62.81; H, 7.49; N, 7.71 Found: C, 62.59; H, 7.59; N, 7.74 3-(3-Butenyl)thiazolium Bromide, 2.41(j) General procedure A was followed by using thiazole (85 mg, mmol) and 4-bromo1-butene (162 mg, 1.2 mmol), giving a white solid Yield: 117 mg (0.53 mmol, 53%) H NMR (500.13 MHz, D2O): δ 8.31 (d, 1H, 3JHH = 5.0 Hz, thi C4/5-H), 8.16 (d, 1H, HH J = 5.0, thi C4/5-H), 5.84-5.76 (m, 1H, CH2CH2CH=CH2), 5.08 (d, 1H, 3JHH = 15.0 Hz, CH2CH2CH=CHHcis), 4.99 (d, 1H, 3JHH = 20.0 Hz, CH2CH2CH=CHHtrans), 4.65 (t, 2H, 3JHH = 7.5 Hz, CH2CH2CH=CH2), 2.70 (q, 2H, 3JHH = 6.7 Hz, CH2CH2CH=CH2) The proton of NHC on the thiazolium ring was not observed due to exchange with deuterium C{1H} NMR (125.03 MHz, D2O): δ 136.9 (thi C2), 13 132.6 (CH2CH2CH=CH2), 125.7 (thi C4/5), 119.5 (CH2CH2CH=CH2), 54.7 (CH2CH2CH=CH2), 33.8 (CH2CH2CH=CH2) MS (ESI, positive mode) m/z (%): 140.0538 (100) [M-Br]+ (calcd 140.0534, dev 2.9 ppm) Anal Calc for C7H10BrNS: C, 38.19; H, 4.58; N, 6.36; S, 14.57;Br, 36.30 Found: C, 38.13; H,4.55; N, 6.29; S, 14.35; Br, 36.05 3-(3-Butenyl)-4,5-dimethylthiazolium Bromide, 2.41(l) General procedure A was followed using 4,5-dimethylthiazole (113 mg, 1mmol) and 4-bromo-1-butene (162 mg, 1.2 mmol), giving a white solid Yield: 243 mg (0.98 mmol, 98%) 1H NMR (500.13 MHz, D2O): δ 9.59 (s, 1H, thi C2-H), 5.85-5.80 (m, 1H, CH2CH2CH=CH2), 5.11 (d, 1H, 3JHH = 10.0 Hz, CH2CH2CH=CHHcis), 5.02 (d, 202 Synthesis, Structure and Catalytic Application of Novel Carbene Complexes with Benzothiazolin-2-ylidene Ligands Chapter Three: Experimental 1H, Experimental JHH = 20.0 Hz, CH2CH2CH=CHHtrans), 4.51 (t, 2H, JHH = 5.0 Hz, CH2CH2CH=CH2), 2.65 (q, 2H, 3JHH = 6.7 Hz, CH2CH2CH=CH2), 2.53 (s, 3H, CH3), 2.44 (s, 3H, CH3) 13 C{1H} NMR (125.03 MHz, D2O): δ 153.6 (thi C2), 141.9 (thi C4/5), 133.7 (CH2CH2CH=CH2), 132.6 (thi C4/5), 119.6 (CH2CH2CH=CH2), 52.7 (CH2CH2CH=CH2), 32.9 (CH2CH2CH=CH2), 11.7 (CH3), 10.9 (CH3) MS (ESI, positive mode) m/z (%): 168.0851 (100) [M-Br]+ (calcd 168.0847, dev 2.4 ppm) Anal Calc for C9H14BrNS: C, 43.56; H, 5.69; N, 5.64 Found: C, 43.55; H, 5.59; N, 5.57 1-(3-methyl-but-3-enyl)-3-methylimidazolium Bromide, 2.41(m) General procedure A was followed using 1-methyl imidazole (82 mg, mmol) and 4bromo-3-methyl-butene (179 mg, 1.2 mmol), giving a yellow oil Yield: 51 mg (0.22 mmol, 22%) 1H NMR (500 MHz, D2O): δ 8.76 (s, 1H, im C2-H), 7.53 (s, 1H, Ar-H), 7.46 (s, 1H, Ar-H), 4.84 (s, 1H, CH2CH2(CH3)C=CHHcis), 4.65 (s, 1H, CH2CH2(CH3)C=CHHtrans), 4.37 (t, 2H, 3JHH = 6.8 Hz, CH2CH2(CH3)C=CH2), 3.91 (s, 3H, CH3), 2.61 (t, 2H, 3JHH = 6.6 Hz, CH2CH2(CH3)C=CH2) 13 C{1H} NMR CH2CH2(CH3)C=CH2), 1.78 (s, 3H, (100 MHz, D2O): δ 141.5 (CH2CH2CH(CH3)=CH2), 136.3 (NHC), 123.8 (Ar-C), 122.7 (Ar-C), 114.1 (CH2CH2CH(CH3)=CH2), 47.9 (CH2CH2CH(CH3)=CH2), 37.9 (CH2CH2CH(CH3)=CH2), 36.9 (CH3), 21.4 (CH2CH2CH(CH3)=CH2) MS (ESI) m/z (%): 152 (100) [M - Br]+ Anal Calc for C9H16BrN2: C, 46.56; H, 6.95; N, 12.07 Found: C, 44.70; H, 6.60; N, 11.68 1-(4-Methyl-pent-3-enyl)-3-methylimidazolium Bromide, 2.41(n) General procedure A was followed using 1-methylimidazole (82 mg, mmol) and 5bromo-2-methylpentene (196 mg, 1.2 mmol), giving a yellow oil Yield: 184 mg (0.75 203 Synthesis, Structure and Catalytic Application of Novel Carbene Complexes with Benzothiazolin-2-ylidene Ligands Chapter Three: Experimental Experimental mmol, 75%) 1H NMR (400 MHz, D2O): δ 8.72 (s, 1H, im C2-H), 7.51 (s, 1H, im C4/5-H), 7.44 (s, 1H, im C4/5-H), 5.16 (t, 1H, JHH = 8.8 Hz, CH2CH2CH=C(CH3)(CH3)), 4.23 (t, 2H, 3JHH = 6.4 Hz, CH2CH2CH=C(CH3)(CH3)), 3.91 (s, 3H, CH3), 2.55 (q, 2H, 3JHH = 6.8 Hz, CH2CH2CH=C(CH3)(CH3)), 1.69 (s, 3H, CH3), 1.42 (s, 3H, CH3) 13C{1H} NMR (100 MHz, D2O): δ 138.1 (im-C2), 136.3 (CH2CH2CH=C(CH3)(CH3)), 123.7 (im C4/5), 122.8 (im C4/5), 118.6 (CH2CH2CH=C(CH3)(CH3)), 49.7 (CH2CH2CH=C(CH3)(CH3)), 36.1 (CH3), 28.7 (CH2CH2CH=C(CH3)(CH3)), 25.3 (CH2CH2CH=C(CH3)(CH3)), 17.1 (CH2CH2CH=C(CH3)(CH3)) MS (ESI, positive mode) m/z (%): 165.1387 (100) [MBr]+ (calcd 165.1392, dev -3.0 ppm) This compound was found to be too hygroscopic to allow for satisfactory elemental analysis 1-(hex-3-enyl)-3-methylimidazolium Bromide, 2.41(o) General procedure A was followed using 1-methyl imidazole (82 mg, mmol) and 1bromo-hex-3-ene (196 mg, 1.2 mmol), giving a yellow oil Yield: 81 mg (0.33 mmol, 33%) 1H NMR (400 MHz, D2O): δ 8.74 (s, 1H, im C2-H), 7.52 (s, 1H, Ar-H), 7.44 (s, 1H, Ar-H), 5.59 (q, 1H, 3JHH = 6.10 Hz, CH2CH2CH=CHCH2CH3), 5.34 (q, 1H, 3JHH = 6.13 Hz, CH2CH2CH=CHCH2CH3), 4.25 (t, 2H, JHH CH2CH2CH=CHCH2CH3), 3.89 (s, 3H, CH3), 2.60 (q, 2H, = 6.13 Hz, JHH = 6.80 Hz, CH2CH2CH=CHCH2CH3), 1.82 (p, 2H, 3JHH = 5.80 Hz, CH2CH2CH=CHCH2CH3), 0.78 (t, 3H, 3JHH = 7.60 Hz, CH2CH2CH=CHCH2CH3) 13 C{1H} NMR (100 MHz, D2O): δ 137.2 (NHC), 123.8 (Ar-C), 123.4 (CH2CH2CH=CHCH2CH3), 122.7 (Ar-C), 49.5 (CH2CH2CH=CHCH2CH3), 36.1 (CH3), 27.9 (CH2CH2CH=CHCH2CH3), 20.3 (CH2CH2CH=CHCH2CH3), 13.8 (CH2CH2CH=CHCH2CH3) MS (ESI) m/z (%): 165 204 Synthesis, Structure and Catalytic Application of Novel Carbene Complexes with Benzothiazolin-2-ylidene Ligands Chapter Three: Experimental Experimental (100) [M-Br]+ Anal Calc for C10H17BrN2: C, 48.99; H, 6.99; N, 11.43 Found: C, 47.78; H, 7.01; N, 11.88 1-(3-Butenyl)-3-methylbenzimidazolium Bromide, 2.41(p) General procedure B was followed using 1-methylbenzimidazole (132 mg, mmol) and 4-bromo-1-butene (162 mg, 1.2 mmol), giving an off-white solid Yield: 264 mg (0.99 mmol, 99%) 1H NMR (500.13 MHz, D2O): δ 7.91-7.88 (m, 1H, Ar-H), 7.857.82 (m, 1H, Ar-H), 7.71-7.66 (m, 2H, Ar-H), 5.88-5.76 (m, 1H, CH2CH2CH=CH2), 5.02 (d, 1H, 3JHH = 10.0 Hz,CH2CH2CH=CHHcis), 4.92 (d, 1H, 3JHH = 18.0 Hz, CH2CH2CH=CHHtrans), 4.56 (t, 2H, 3JHH = 6.8 Hz, CH2CH2CH=CH2), 4.06 (s, 3H, NCH3), 2.71 (q, 2H, 3JHH = 6.80 Hz, CH2CH2CH=CH2) The proton of im C2 on the benzimidazolium ring was not observed, due to the exchange with deuterium 13C{1H} NMR (125.03 MHz, D2O): δ 139.9 (im-C2), 133.6 (CH2CH2CH=CH2), 127.2 (Ar-C), 119.1 (CH2CH2CH=CH2), 113.5, 113.3 (Ar-C), 46.5 (CH2CH2CH=CH2), 33.1 (CH2CH2CH=CH2), 33.0 (NCH3) Anal Calc for C12H15BrN2: C, 53.95; H, 5.66; N, 10.49 Found: C, 53.66; H, 5.63; N, 10.44 rac-1,7-Dimethyl-6,7-dihydro-5H-pyrrole[1,2-r]imidazolium Bromide, 2.42(f) Diffusion of Et2O into a concentrated CH2Cl2 solution of 2.42(f) yielded transparent crystals suitable for X-ray diffraction studies 1H NMR (500.13 MHz, D2O): δ 7.24 (s, 2H, im C4/5-H), 4.28-4.23 (m, 1H, NCH2), 4.15-4.10 (m, 1H, NCH2), 3.77 (s, 3H,NCH3), 3.65-3.59 (m, 1H, CH β to N), 2.98-2.92 (m, 1H, CH2 γ to N, overlap with H anti to CH3), 2.40-2.34 (m, 1H, CH2 γ to N, overlap with H syn to CH3), 1.39 (d, 3H, CHCH3, 3JHH = 10.0 Hz) 1H NMR chemical shifts of hydrogens on the carbon atom γ to N assigned by analogy with those of 2.42(n) (obtained with gs-NOESY 205 Synthesis, Structure and Catalytic Application of Novel Carbene Complexes with Benzothiazolin-2-ylidene Ligands Chapter Three: Experimental experiments) 13 Experimental C{1H} NMR (125.03 MHz, D2O): δ 154.63 (im C2), 126.84 (im C4/5), 117.07 (im C4/5), 46.78 (NCH2), 34.74 (NCH3), 34.33 (CH β to N), 31.12 (CH2 γ to N), 15.73 (CHCH3) MS (ESI, positive mode) m/z (%): 37.1075 (100) [MBr]+ (calcd 137.1079, dev -2.9 ppm) Anal Calc for C8H13N2Br: C, 44.26; H, 6.04; N, 12.90 Found: C, 43.92; H, 6.04; N, 12.88 rac-1-Butyl-7-methyl-6,7-dihydro-5H-pyrrolo[1,2-r]imidazolium Bromide, 2.42(g) H NMR (400 MHz, D2O): δ 7.36 (s, 1H, im C4/5-H), 7.32 (s, 1H, im C4/5-H), 4.33- 4.26 (m, 1H, NCH2), 4.19-4.17 (m, 1H, NCH2, overlap with NCH2CH2CH2CH3), 4.11 (t, 2H, 3JHH = 5.4 Hz, NCH2CH2CH2CH3), 3.70-3.62 (m, 1H, CH β to N), 3.04-2.96 (m, 1H, CH2 γ to N, overlap with residual solvent peak), 2.42-2.37 (m, 1H, CH2 γ to N), 1.81 (p, 1H, 3JHH = 9.20 Hz, NCH2CH2CH2CH3), 1.43 (d, 3H, 3JHH = 9.0 Hz, CHCH3), 1.34 (sextet, 2H, 3JHH = 8.4 Hz, NCH2CH2CH2CH3), 0.92 (t, 3H, 3JHH = 7.4 Hz, NCH2CH2CH2CH3) 13C{1H} NMR (100 MHz, D2O): δ 154.4 (im C2), 121.0 (im C4/5), 117.7 (im C4/5), 49.0 (NCH2CH2CH2CH3), 46.9 (NCH2), 34.1 (CH β to N), 31.8 (NCH2CH2CH2CH3), 31.1 (CH2 γ to N), 19.3 (NCH2CH2CH2CH3), 17.2 (CHCH3), 13.1 (NCH2CH2CH2CH3) MS (ESI, positive mode) m/z (%): 179.1543 (100) [M-Br]+ (calcd 179.1548, dev -2.8 ppm) This compound was found to be too hygroscopic for satisfactory elemental analysis rac-7-Methyl-6,7-dihydro-5H-pyrrolo[1,2-r]-4,5-dimethylthiazolium Bromide, 2.42(l) H NMR (500.13 MHz, D2O): δ 4.55 (m,1H, NCH2), 4.43 (m, 1H, NCH2), 3.94 (m, 1H, m, 1H, CH β to N), 3.02-2.98 (m, 1H, CH γ to N), 2.50 (s, 3H, CCH3), 2.46-2.42 (m, 1H, CH2 γ to N), 2.40 (s, 3H, CCH3), 1.51 (d, 3H, 3JHH = 6.95 Hz, CHCH3) 206 Synthesis, Structure and Catalytic Application of Novel Carbene Complexes with Benzothiazolin-2-ylidene Ligands Chapter Three: Experimental Experimental C{1H} NMR (125.03 MHz, D2O): δ 175.4 (thi C2), 136.4, 134.7 (thi C4/5), 51.6 13 (NCH2), 38.5 (CH β to N), 33.2 (CH2 γ to N), 18.2 (CHCH3), 11.9 (CCH3), 10.3 (CCH3) Anal Calc for C9H14SNBr0.5H2O: C, 39.28; H, 6.23; N, 5.09 Found: C, 39.03; H, 5.79; N, 4.85 rac-1-Methyl-7-isopropyl-6,7-dihydro-5H-pyrrolo[1,2-r]imidazolium Bromide, 2.42(n) H NMR (500.13 MHz, D2O): δ 7.56 (d, 1H, 3JHH = 1.9 Hz, im C4/5-H), 7.44 (d, 1H, JHH = 1.9 Hz, im C4/5-H), 4.27-4.33 (m, 1H, NCH2), 4.13-4.19 (m, 1H, NCH2), 3.88 (s, 3H, NCH3), 3.73 (m, 1H, NCH2), 2.78-2.87 (m, 1H, H γ to N and anti to iPr), 2.432.51 (m, 1H, H γ to N and syn to iPr), 2.26-2.36 (m, 1H, CH(CH3)2), 0.99 (d, 3H, 3JHH = 6.9 Hz, CH(CH3)2), 0.73 (d, 3H, 3JHH = 6.8 Hz, CH(CH3)2) 13C{1H} NMR (125.03 MHz, D2O): δ 153.8 (im C2), 127.2 (im C4/5), 117.3 (im C4/5), 47.5 (NCH2), 42.3 (CH β to N), 34.8 (NCH3), 29.2 (CH(CH3)2), 27.3 (CH2 γ to N), 19.6 (CH(CH3)2), 16.5 (CH(CH3)2) MS (ESI, positive mode) m/z (%): 165.1385 (100) [M-Br]+ (calcd 165.1392, dev -4.2 ppm) Anal Calc for C10H17N2Br (Mr ) 245.16): C, 48.99; H, 6.99; N, 11.43 Found: C, 48.77; H, 6.95; N, 11.38 rac-1,7-Dimethyl-6,7-dihydro-5H-pyrrole[1,2-r]benzimidazolium Bromide, 2.42(p) H NMR (500.13 MHz, D2O): δ 7.72 (m, 1H,Ar-H), 7.66 (m, 1H, Ar-H), 7.58 (m, 2H, Ar-H), 4.51 (m, 1H, NCH2), 4.38 (m, 1H, NCH2), 4.01 (s, 3H, NCH3), 3.94 (m, 1H, CH β to N), 3.19 (m, 1H, CH2 γ to N), 2.58 (m, 1H, CH2 γ to N),1.61 (d, 3H, 3JHH = 6.95 Hz, CHCH3) 13C{1H} NMR (125.03 MHz, D2O): δ 160.6 (im C2), 136.4, 128.2, 125.9, 125.8,112.8, 112.7 (Ar-C), 45.1 (NCH2), 34.1 (CH β to N), 31.7 (CH2 γ to N), 207 Synthesis, Structure and Catalytic Application of Novel Carbene Complexes with Benzothiazolin-2-ylidene Ligands Chapter Three: Experimental Experimental 31.4 (NCH3), 15.9 (CH(CH3)2) Anal Calc for C12H15N2Br.H2O: C, 50.54; H, 6.01; N, 9.82 Found: C, 50.16; H, 5.83; N, 9.49 Procedure for the Catalytic Coupling of Azolium Salts A 60 mL Young Schlenk was charged with bis(cycloocta-1,5-diene)nickel(0) (10 mg, 0.04 mmol, mol % in most cases), a phosphine or NHC ligand (0.08 mmol, 11 mol %), and the substrate (0.73 mmol, equiv) in a glovebox DMF was then syringed into the reaction vessel under a flow of argon, and the yellow solution was heated to reaction temperature (50 °C in most cases) The solution was stirred for the required time (1 h in most cases) The solvent was then removed in vacuo and the residue dissolved in D2O and submitted for 1H NMR spectroscopy The conversion to annulated product was calculated by comparing the integration values of N-Me protons of the starting material and the product (no other products were detected apart from NHC or phosphine ancillary ligand) Complex 2.43 from Oxidative Addition of 2.41(f) to Pt(0) A solution of THF (4 mL) of 2.41(f) (91 mg, 0.27 mmol) was transferred to a mixture of Pt(nbe)3 (143 mg, 0.30 mmol) and IMes (91 mg, 0.30 mmol) which was dissolved in THF (4 mL) The mixture was heated at 55 °C for 50 The solvent was removed under vacuum The off-white oil was washed several times with hexane and Et2O and dried under vacuum Yield: 295 mg (0.41 mmol, 45%) 1H NMR (400 MHz, CD2Cl2): δ -18.06 (s, 1H, MH), 7.48 (d, 2H, Ar-H), 7.08-6.89 (m, 6H, Ar-H), 5.49-5.41 (m, 1H, CH2CH2CH=CH2), 4.93-4.82 (m, 2H, CH2CH2CH=CH2), 3.75 (t, 2H, 3JHH = 7.4 Hz, CH2CH2CH=CH2), 3.35 (q, 2H, 3JHH = 6.93 Hz, CH2CH2CH=CH2), 3.21 (s, 3H, CH3), 2.31 (s, 6H, CH3), 2.13 (s, 12H, CH3) 208 Synthesis, Structure and Catalytic Application of Novel Carbene Complexes with Benzothiazolin-2-ylidene Ligands ... NMR ( 125 . 03 MHz, D2O): δ 135 .2 (im- 13 C2), 133 .3 (CH2CH2CH=CH2), 122 .4 (im C4/5), 118.8 (CH2CH2CH=CH2), 49 .3 (CH2CH2CH2CH3), 48.8 (CH2CH2CH=CH2), 33 .8 (CH2CH2CH=CH2), 31 .2 (CH2CH2CH2CH3), 18.7... CH2CH2CH=CH2), 4. 93- 4. 82 (m, 2H, CH2CH2CH=CH2), 3. 75 (t, 2H, 3JHH = 7.4 Hz, CH2CH2CH=CH2), 3. 35 (q, 2H, 3JHH = 6. 93 Hz, CH2CH2CH=CH2), 3 .21 (s, 3H, CH3), 2. 31 (s, 6H, CH3), 2. 13 (s, 12H, CH3) 20 8... NMR ( 125 . 03 MHz, D2O): δ 141.5 (im-C2), 136 .3, 135 .3 (Ar-C), 133 .1 (CH2CH2CH=CH2), 130 .8, 129 .2, 124 .1, 1 23 .0 (Ar-C), 119.4 (CH2CH2CH=CH2), 49.1 (CH2CH2CH=CH2), 33 .9 (CH2CH2CH=CH2), 20 .2 (CH3),