SYNTHESIS, STRUCTURE AND CATALYTIC APPLICATION OF NOVEL CARBENE COMPLEXES WITH BENZOTHIAZOLIN 2 YLIDENE LIGANDS 3

Diffusion of Et2O into a concentrated CH2Cl2 solution yielded transparent crystals suitable for X-ray diffraction studies.. Diffusion of Et2O into a concentrated CH2Cl2solution yielded t

diphenylphosphanylpyridine, pyrazine, trans-1,2-pyridyl)ethylene, 1,2-

bis(pyridyl)ethane, 4,4’-bypyridine, 2-iodo-propane, 2-aminopyridine, 3-iodopyridine,

4-tert-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

1

H, 13C{1H}, 31P{1H}, 195Pt{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

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

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, 3

JHH = 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 CH2Cl2solution 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,

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)

13

C{1H} NMR (75.5 MHz, CDCl3): δ 165.0 (NCS), 140.1, 131.3 (Ar–C), 130.0

(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 ray diffraction studies Yield: 5.55 g (21.50 mmol, 78%) 1H NMR (500 MHz, CDCl3):

X-δ 12.09 (s, 1H, NCH), 8.43 (d, 3

JHH = 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,

CH 2CH2CH3), 2.17 (pseudo sext, 2H, CH2CH 2CH3), 1.08 (t, 3H, 3JHH =7.3 Hz,CH2CH2CH 3) 13C{1H} NMR (125MHz,CDCl3): δ 164.9 (NCH), 140.2, 131.4, 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

3-Isopropylbenzothiazolium triiodide, D

D was prepared similarly to A from benzothiazole (3.74 g, 27.65 mmol) and

2-iodo-propane (15.33 g, 90.16 mmol) at 100 °C for 2 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,

3

JHH = 6.6 Hz, 1H, CH(CH3)2), 1.93 (d, 3JHH = 6.9 Hz, 6H, CH(CH 3)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, 1 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, 3

JHH = 7.55 Hz, 2H, Ar-H), 7.25 (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

7.53-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, 1 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 2 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

3 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,

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

5 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, 3

JHH = 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) 13C{1H} NMR (75.5 MHz, CDCl3): δ 191.9 (NCS), 162.6 (CHO), 142.5, 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

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, 1 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%) 1

H NMR (500 MHz, DMSO-d6): δ 8.13 (d, 2H, 3

JHH = 8.2 Hz, Ar–H), 7.95 (d, 2H, 3

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=CHH trans), 5.36 (broad d, 2H, 3JHH = 10.1

Hz, CH2CH=CHH cis) 13C{1H}NMR(125 MHz, DMSO-d6): δ 203.0 (NCS), 142.7,

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) 13C{1H} NMR (125 MHz, DMSO-d6): δ 212.2 (NCS), 142.6,

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

MHz, DMSO-d6): δ 8.19 (d, 2H, 3

JHH = 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

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, 2 mmol) and

Pd(OAc)2 (225 mg, 1 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,

CH 2CH2CH3), 2.17 (br, m, 4H, CH2CH 2CH3), 1.08 (t, 6H, 3JHH = 6.0 Hz,

CH2CH2CH 3) 13C{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, 1 mmol) and PPh3 (525 mg, 2 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)

31

P{1H}NMR(202.43 MHz, CDCl3): δ 27.3 (s, PPh3) 13C{1H} NMR(125 MHz,

CDCl3): δ 208.4 (NCS), 167.8, 142.2, 136.5 (Ar–C), 134.5 (d, 2/3

JCP = 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

(Ar–C), 128.8 (d, 4JCP = 2.73 Hz, Ar–C), 128.4 (d, 2/3JCP = 10.90 Hz, Ar–C), 128.2, 126.6, 125.07, 121.7, 115.2 (Ar–C), 59.5 (NCH2) MS (ESI, positive mode) m/z (%):

Complex 2.9(b) was prepared similarly to 2.9(a) from 2.2(b) (887 mg, 1 mmol) and

PPh3 (525 mg, 2 mmol) Yield: 762 mg (1.08 mmol, 54%) 1H NMR (500 MHz, CDCl3): δ 7.68–7.64 (m, 6H, Ar–H), 7.61 (d, 1H, 3

JHH = 7.6 Hz, Ar–H) 7.43–7.41 (m, 1H, Ar–H), 7.36–7.32 (m, 5H, Ar–H), 7.25–7.22 (m, 6H, Ar–H), 4.81 (dt, 1H, 3JHH = 12.5 Hz, 2JHH = 5.4 Hz, CHHCH2CH3), 4.05 (dt, 1H, 3JHH = 12.5 Hz, 2JHH = 5.4 Hz,

[M − Br + CH3OH]+ Anal Calc for C28H26Br2NPPdS (M = 705.78): C, 47.65; H, 3.71; N, 1.98; S, 4.54 Found: C, 47.06; H, 3.52; N, 1.79; S, 4.89

cis-Dibromo(3-benzylbenzothiazolin-2-ylidene)(tricyclohexylphosphine)Pd(II),

2.10(a)

Complex 2.10(a) was prepared similarly to 2.9(a) from 2.2(a) (983 mg, 1 mmol) and

PCy3 (561 mg, 2 mmol) The yellow precipitate was obtained by filtration Yield: 1.02

g (1.32 mmol, 66%) 1H NMR (500 MHz, CDCl3): δ 7.86 (d, 1H, 3

JHH = 8.2 Hz, Ar–

H), 7.44–7.31 (m, 8H, Ar–H), 6.69 (d, 2H, 2JHH = 15.8 Hz, NCHH), 6.14 (d, 2H, 2JHH

= 15.8 Hz, NCHH), 2.25–2.12 (m, 6H, CH2), 1.80 (broad s, 7H, CH2), 1.66–1.58 (m, 10H, CH2), 1.25–1.12 (m, 7H, CH2), 0.91 (br, s, 3H, PCH) 31P{1H} NMR (202.43

MHz, CDCl3): δ 44.7 (s, PCy3) 13C{1H} NMR (125 MHz, CDCl3): δ 208.7 (NCS),

142.8, 135.6, 132.8, 128.8, 128.4, 127.6, 127.1, 125.6, 122.0, 115.8 (Ar–C), 61.1 (NCH2), 36.6 (d, 1JCP = 21.9 Hz, PCH), 30.5, 29.8 (CH2), 27.5 (d, 2/3JCP = 10.9 Hz,

CH2), 26.0 (CH2) MS (ESI, positive mode) m/z (%): 692 (100) [M − Br]+

Anal Calc for C32H44Br2NPPdS (M= 771.97): C, 49.79; H, 5.74; N, 1.81; S, 4.15 Found: C, 49.37; H, 5.78; N, 1.89; S, 3.95

cis-Dibromo(3-propylbenzothiazolin-2-ylidene)(tricyclohexylphosphine)Pd(II),

2.10(b)

Complex 2.10(b) was prepared similarly to 2.9(a) from 2.2(b) (887 mg, 1 mmol) and

PCy3 (561 mg, 2 mmol) The yellow precipitate was obtained and filtered Yield: 1.01

g (1.40 mmol, 70%) 1H NMR (500 MHz, CDCl3): δ 7.86 (d, 1H, 3

JHH = 8.2 Hz, Ar–H), 7.66 (d, 1H, 3JHH = 8.9 Hz, Ar–H), 7.57 (t, 1H, 3JHH = 7.7 Hz, Ar–H), 7.49 (t, 1H,

3

JHH = 7.6 Hz, Ar–H), 5.39 (dt, 1H, 2JHH = 12.5, 3JHH =4.6 Hz, CHHCH2CH3), 4.46 (dt, 1H, 2JHH =12.5, 3JHH = 4.6 Hz, CHHCH2CH3), 2.72 (m, 1H, CH2CHHCH3), 1.95 (m, 1H, CH2CHHCH3), 2.19 (br s, 7H, CH2), 1.80–1.62 (m, 23H, CH2), 1.16 (t, 3H,

3

JHH = 7.3 Hz, CH2CH2CH 3), 0.86–0.83 (m, 3H, PCH) 31P{1H} NMR (202.43 MHz,

CDCl3): δ 43.7 (s, PCy3) 13C{1H} NMR (125 MHz, CDCl3): δ 206.0 (NCS), 142.3,

135.8, 127.2, 125.6, 122.3, 114.2 (Ar–C), 59.1 (CH2CH2CH3), 36.5 (d, 1JCP = 21.9 Hz, PCH), 30.7, 29.6 (CH2), 27.6 (d, 2/3JCP = 8.2 Hz, CH2), 27.5 (d, 2/3JCP = 6.4 Hz, CH2), 26.9 (CH2), 20.7 (CH2CH2CH3), 11.7 (CH2CH2CH3) MS (ESI, positive mode) m/z

(%): 644 (100) [M − Br]+

Anal Calc for C28H44Br2NPPdS (M = 723.92): C, 46.46;

H, 6.13; N, 1.93; S, 4.43 Found: C, 46.43; H, 6.35; N, 2.05; S, 4.31

cis-Dibromo(3-benzylbenzothiazolin-2-ylidene)(2-diphenylphosphanylpyridine)-Pd(II), 2.11(a)

Complex 2.11(a) was prepared similarly to 2.9(a) from 2.2(a) (983 mg, 1 mmol) and

PPh2Py (527 mg, 2 mmol) The white precipitate obtained was filtered and washed with Et2O Yield: 906 mg (1.20 mmol, 60%) 1H NMR (500 MHz, CDCl3): δ 8.20 (d, 1H, 3JHH = 5.1 Hz, Ar–H), 7.97–7.93 (m, 2H, Ar–H), 7.73–7.69 (m, 2H, Ar–H), 7.60–7.57 (m, 3H, Ar–H), 7.51–7.49 (m, 2H, Ar–H), 7.47–7.40 (m, 1H, Ar–H), 7.36–7.32 (m, 2H, Ar–H), 7.31–7.20 (m, 8H, Ar–H), 7.15–7.13 (m, 1H, Ar–H), 7.10–7.07 (m, 1H, Ar–H), 6.78 (d, 1H, 2JHH = 15.5 Hz, NCHH), 5.26 (d, 1H, 2JHH = 15.5 Hz,

NCHH) 31P{1H} NMR (202.43 MHz, CDCl3): δ 24.5 (s, PPh2Py) 13C{1H} NMR

(125 MHz, CDCl3): δ 207.7 (NCS), 156.0, 155.4 (Ar–C), 149.5 (d, 1/2

JCP = 16.4 Hz, Ar–C), 142.2, 136.5 (Ar–C), 135.99 (d, 3JCP =8.2 Hz, Ar–C), 135.93 (d, 2/3JCP =10.9

Hz, Ar–C), 135.8 (Ar–C), 134.2 (d, 2/3JCP = 10.9 Hz, Ar–C), 133.0, 131.5 (Ar–C), 131.0 (d, 4JCP =2.7 Hz, Ar–C), 130.5, 130.3, 130.2, 129.8, 128.9, 128.8, 128.5, 128.4 (Ar–C), 128.2 (d, 2/3JCP = 10.9 Hz, Ar–C), 127.9, 126.5, 124.9 (Ar–C), 124.1 (d, 4JCP

= 2.7 Hz, Ar–C), 121.6, 115.3 (Ar–C), 60.2 (NCH2) MS (ESI, positive mode) m/z

Complex 2.11(b) was prepared similarly to 2.9(a) from 2.2(b) (887 mg, 1 mmol) and

PPh2Py (527 mg, 2 mmol) The white precipitate obtained was filtered and washed

with Et2O Yield: 1.02 g (1.44 mmol, 72%) 1H NMR (500 MHz, CDCl3): δ 8.23 (d, 1H, 3JHH = 4.4 Hz, Ar–H), 7.97–7.92 (m, 2H, Ar–H), 7.75–7.70 (m, 2H, Ar–H), 7.61–7.55 (m, 3H, Ar–H), 7.45–7.39 (m, 3H, Ar–H), 7.36–7.32 (m, 3H, Ar–H), 7.27–7.25 (m, 1H, Ar–H), 7.22–7.19 (m, 2H, Ar–H), 7.10–7.07 (m, 1H, Ar–H), 5.04 (dt, 1H,

2

JHH = 12.6 Hz, 3JHH = 4.9 Hz, CHHCH2CH3), 4.28 (dt, 1H, 2JHH = 12.6 Hz, 3JHH =

4.9 Hz, CHHCH2CH3), 2.39 (m, 1H, CH2CHHCH3), 1.88 (m, 1H, CH2CHHCH3), 1.07 (t, 3H, 3JHH = 7.3 Hz, CH2CH2CH 3) 31P{1H} NMR (202.43 MHz, CDCl3): δ

24.6 (s, PPh2Py) 13C{1H} NMR (125 MHz, CDCl3): δ 205.3 (NCS), 156.0, 155.3

(Ar–C), 149.50 (d, 1/2JCP = 17.3 Hz, Ar–C), 142.0, 136.2 (Ar–C), 135.9 (d, 3JCP = 9.6

Hz, Ar–C), 134.2 (d, 2/3JCP = 10.0 Hz, Ar–C), 131.5 (d, 4JCP = 1.8 Hz, Ar–C), 131.0 (d,

4

JCP = 1.8 Hz, Ar–C), 130.5, 130.3, 130.2, 129.8, 128.8 (Ar–C), 128.4 (d, 2/3JCP = 11.9

Hz, Ar–C), 128.1 (d, 2/3JCP = 10.9 Hz, Ar–C), 126.6, 124.9 (Ar–C), 124.1 (d, 4JCP =

2.7 Hz, Ar–C), 121.8, 113.9 (Ar–C), 57.4 (CH2CH2CH3), 21.2 (CH2CH2CH3), 11.5 (CH2CH2CH3) MS (ESI, positive mode) m/z (%): 627 (100) [M − Br]+

Anal Calc for C27H25Br2N2PPdS (M = 706.77): C, 45.88; H, 3.57; N, 3.96; S, 4.54 Found: C, 45.32; H, 3.52; N, 4.01; S, 4.35

3.2.5 Synthesis of Complexes 2.12-2.16 (Chapter Two, Section 2.6)

trans-Dibromo(3-benzylbenzothiazolin-2-ylidene)(pyridine)palladium(II), 2.12(a)

Pyridine (5 mL) was added to complex 2.2(a) (60 mg, 0.06 mmol) and the mixture

was stirred at r.t for overnight The clear yellow solution was evaporated under vacuum The yellow solid was dissolved in CH2Cl2 and Et2O was added to induce precipitation The product was washed with Et2O and dried Diffusion of Et2O into a sample solution in CH2Cl2 yielded yellow crystals suitable for X-ray diffraction

studies Yield: 68 mg (0.12 mmol, 98 %) 1H NMR (500 MHz, CDCl3): δ 9.01 (m, 2H, Ar-H), 7.81 (d, 3JHH = 8.9 Hz, 1H, Ar-H), 7.76 (tt, 3JHH = 1.6 Hz, 2JHH = 7.9 Hz, 1H, Ar-H), 7.57 (d, 3JHH = 6.9 Hz, 2H, Ar-H), 7.44 (d, 3JHH = 8.2 Hz, 1H, Ar-H), 7.40-7.31 (m, 7H, Ar-H), 6.54 (s, 2H, CH2); 13C{1H} NMR (125 MHz, CDCl3): δ

195.7 (NCS), 162.7, 147.9, 142.8, 130.9, 129.6, 129.3, 129.1, 128.5, 128.2, 127.9, 127.6, 126.7, 125.1, 124.7, 124.5, 121.8, 115.1 (Ar-C), 60.1 (CH2); MS (ESI, positive

mode) m/z (%): 571 (100) [M + H]+ Anal Calc for C19H16Br2PdN2S.CH2Cl2.py (M = 734.67): C, 40.87; H, 3.16; N, 5.72; S, 4.36 Found: C, 40.99; H, 3.19; N, 5.72; S, 4.96

trans-Dibromo(3-propylbenzothiazolin-2-ylidene)(pyridine)palladium(II), 2.12(b)

Complex 2.12(b) was prepared similarly to 2.12(a) from 2.2(b) (79 mg, 0.09 mmol)

Diffusion of Et2O into a solution in CH2Cl2 yielded yellow crystals suitable for X-ray diffraction studies Yield: 89 mg (0.17 mmol, 98%) 1H NMR (500 MHz, CDCl3): δ 9.04 (d, 3JHH = 6.4 Hz, 2H, Ar-H), 7.82 (d, 3JHH = 8.0 Hz, 1H, Ar-H), 7.79 (t, 3JHH = 7.6 Hz, 1H, Ar-H), 7.68 (d, 3JHH = 8.2 Hz, 1H, Ar-H), 7.51 (t, 3JHH = 7.9 Hz, 1H, Ar-H), 7.42 (t, 3JHH = 7.6 Hz, 1H, Ar-H), 7.37 (t, 3JHH = 6.9 Hz, 2H, Ar-H), 5.15 (t, 3JHH

= 8.2 Hz, 2H, CH 2CH2CH3), 2.35 (m, 3JHH = 7.9 Hz, 2H, CH2CH 2CH3), 1.22 (t, 3JHH

= 7.6 Hz, 3H, CH2CH2CH 3); 13C{1H} NMR (125 MHz, CDCl3): δ 193.3 (NSC), 154.4, 152.7, 149.8, 142.8, 138.1, 136.7, 126.7, 125.1, 124.7, 121.9, 113.8 (Ar-C),

56.9 (CH2CH2CH3), 22.7 (CH2CH2CH3), 11.7 (CH2CH2CH3); MS (ESI, positive

mode) m/z (%): 443 (40) [M - Br]+ Anal Calc for C15H16Br2N2PdS (M = 522.59): C, 34.47; H, 3.09; N, 5.36; S, 6.14 Found: C, 35.65; H, 2.98; N, 5.54; S, 6.09

Dibromo(µ-pyrazine)bis(3-benzylbenzothiazolin-2-ylidene)dipalladium(II),

2.13(a)

A mixture of 2.2(a) (122 mg, 0.12 mmol) and pyrazine (9.9 mg, 0.12 mmol) was

suspended in CH2Cl2 (5 mL) and stirred at r.t for overnight Et2O (15 mL) was added

to give a yellow precipitate which was collected from filtration Diffusion of Et2O into

a CH2Cl2 solution yielded yellow crystals suitable for X-ray diffraction studies Yield:

64 mg (0.06 mmol, 50 %) 1H NMR (500 MHz, CDCl3): δ 9.22 (s, 4H, Ar-H), 7.83 (d,

3

JHH = 7.6 Hz, 2H, Ar-H), 7.52 (d, 3JHH = 6.9 Hz, 4H, Ar-H), 7.46 (d, 3JHH = 8.2 Hz, 2H, Ar-H), 7.41-7.33 (m, 10H, Ar-H), 6.46 (s, 4H, CH2) 13C{1H} NMR (125 MHz, CDCl3): δ 191.8 (NSC), 148.4, 147.6, 146.9, 146.4, 142.7, 136.7, 133.2, 129.2, 128.7, 127.6, 126.9, 125.4, 121.8, 115.2 (Ar-C), 60.2 (CH2); MS (ESI) m/z (%): 1080 (30)

[M + Na]+. Anal Calc for C32H26Br4N4Pd2S2 (M = 1063.16): C, 36.15; H, 2.46; N, 5.27; S, 6.03 Found: C, 36.83; H, 2.76; N, 4.76; S, 6.25

Dibromo(µ-pyrazine)bis(3-propylbenzothiazolin-2-ylidene)dipalladium(II),

2.13(b)

Complex 2.13(b) was prepared similarly to 2.13(a) from 2.2(b) (127 mg, 0.14 mmol)

and pyrazine (11.5 mg, 0.14 mmol) Yield: 68 mg (0.07 mmol, 50 %) 1H NMR (500 MHz, CDCl3): δ 9.30 (s, 4H, Ar-H), 7.85 (d, 3

JHH = 8.2 Hz, 2H, Ar-H), 7.71 (d, 3JHH = 8.8 Hz, 2H, Ar-H), 7.55 (t, 3JHH = 7.9 Hz, 2H, Ar-H), 7.46 (t, 3JHH = 7.6 Hz, 2H, Ar-H), 5.10 (t, 3JHH = 8.2 Hz, 4H, CH 2CH2CH3), 2.32 (m, 3JHH = 7.8, 4H, CH2CH 2CH3), 1.22 (t, 3JHH = 7.6, 6H, CH2CH2CH 3) 13C{1H} NMR (125 MHz, CDCl3): δ 148.3,

146.9, 142.7, 136.6, 126.9, 125.3, 122.0, 113.9 (Ar-C), 57.2 (CH2CH2CH3), 21.9 (CH2CH2CH3), 11.6 (CH2CH2CH3); MS (ESI) m/z (%): 985 (10) [M - Br +

3CH3OH]+ Anal Calc for C24H26Br4N4Pd2S2 (M = 967.08): C, 29.81; H, 2.71; N, 5.79; S, 6.63 Found: C, 29.92; H, 2.74; N, 5.53; S, 6.15

Dibromo(µ-4,4’-bipyridine)bis(3-benzylbenzothiazolin-2-ylidene)dipalladium(II), 2.14(a)

Complex 2.14(a) was prepared similarly to 2.13(a) from 2.2(a) (122 mg, 0.12 mmol)

and 4, 4’-bipyridine (19 mg, 0.12 mmol) Yield: 86 mg (0.07 mmol, 60 %) 1H NMR

(500 MHz, DMSO-d 6): δ 9.03 (s, 3H, Ar-H), 8.76 (s, 5H, Ar-H), 8.18-8.02 (m, 4H, Ar-H), 7.89 (s, 2H, Ar-H), 7.75-7.51 (m, 8H, Ar-H), 7.37 (s, 4H, Ar-H), 6.63 (s, 4H,

CH2) 13C{1H} NMR (125 MHz, DMSO-d 6): δ 141.9, 134.9, 134.1, 128.6, 128.0, 127.1, 126.9, 125.5, 122.7, 115.8 (Ar-C), 58.2 (CH2) Anal Calc for

C38H30Br4N4Pd2S2.CH2Cl2 (M = 1224.19): C, 38.26; H, 2.63; N, 4.58; S, 5.24 Found:

C, 39.69; H, 2.46; N, 4.69; S, 5.39

Dibromo(µ-4,4’-bipyridine)bis(3-propylbenzothiazolin-2-ylidene)dipalladium(II), 2.14(b)

Complex 2.14(b) was prepared similarly to 2.13(a) from 2.2(b) (100 mg, 0.11 mmol)

and 4, 4’-bipyridine (17.2 mg, 0.11 mmol) Yield: 63 mg (0.06 mmol, 55 %) 1H

NMR (500 MHz, DMSO-d6): δ 9.05 (m, 3H, Ar-H), 8.78 (s, 1H, Ar-H), 8.18 (m, 4H, Ar-H), 8.07 (m, 3H, Ar-H), 7.89 (s, 1H, Ar-H), 7.66 (t, 3JHH = 6.9 Hz, 2H, Ar-H), 7.56 (t, 3JHH = 6.9 Hz, 2H, Ar-H), 5.21 (broad s, 4H, CH2CH2CH3), 2.25 (broad s, 4H,

CH2CH2CH3), 1.14 (broad s, 6H, CH2CH2CH3); MS (ESI) m/z (%): 964 (20) [M -

Br]+ Anal Calc for C30H30Br4N4Pd2S2 (M = 1043.17): C, 34.54; H, 2.90; N, 5.37; S, 6.15 Found: C, 34.90; H, 2.88; N, 5.31; S, 6.08

Dibromo[µ-trans-1,2-bis(4-pyridyl)ethylene]bis(3-benzylbenzothiazolin-2-ylidene)dipalladium(II), 2.15(a)

Complex 2.15(a) was prepared similarly to 2.13(a) from 2.2(a) (215 mg, 0.22 mmol)

and trans-1,2-bis(4-pyridyl)ethylene (40 mg, 0.22 mmol) Yield: 210 mg (0.18 mmol,

H, 2.77; N, 4.81; S, 5.50 Found: C, 40.06; H, 2.71; N, 4.99; S, 5.15

Dibromo[µ-trans-1,2-bis(4-pyridyl)ethylene]bis(3-propylbenzothiazolin-2-ylidene)dipalladium(II), 2.15(b)

Complex 2.15(b) was prepared similarly to 2.13(a) from 2.2(b) (218 mg, 0.24 mmol)

and trans-1,2-bis(4-pyridyl)ethylene (44 mg, 0.24 mmol) Yield: 184 mg (0.17 mmol,

70 %) 1H NMR (500 MHz, DMSO-d 6): δ 8.91 (s, 4H, Ar-H), 8.17 (d, 3

JHH = 7.6 Hz,

4H, Ar-H), 7.81 (s, 4H, Ar-H), 7.72 (s, 2H, CH=CH), 7.66 (t, 3JHH = 7.9 Hz, 2H, H), 7.56 (t, 3JHH = 7.9 Hz, 2H, Ar-H), 5.20 (t, 3JHH = 7.3 Hz, 4H, CH 2CH2CH3), 2.24 (m, 3JHH = 7.4 Hz, 4H, CH2CH 2CH3), 1.14 (t, 3JHH= 6.9 Hz, 6H, CH2CH2CH 3) Anal Calc for C32H32Br4N4Pd2S2 (M = 1069.21): C, 35.95; H, 3.02; N, 5.24; S, 6.00 Found: C, 36.22; H, 2.84; N, 5.00; S, 6.06

Dibromo[µ-1,2-bis(4-pyridyl)ethane]bis(3-benzylbenzothiazolin-2-ylidene)dipalladium(II), 2.16(a)

Complex 2.16(a) was prepared similarly to 2.13(a) from 2.2(a) (100 mg, 0.10 mmol)

and trans-1,2-bis(4-pyridyl)ethylene (18.7 mg, 0.10 mmol) Diffusion of CH2Cl2 into

a sample solution in DMSO yielded orange crystal suitable for X-ray diffraction studies Yield: 71 mg (0.06 mmol, 60 %) 1H NMR (500 MHz, CDCl3): δ 8.92 (d,

(%): 1088 (50) [M - Br]+ Anal Calc for C40H34Br4N4Pd2S2 (M = 1167.31): C, 41.16;

H, 2.94; N, 4.80; S, 5.49 Found: C, 41.06; H, 2.76; N, 4.66; S, 5.53

Dibromo[µ-1,2-bis(4-pyridyl)ethane]bis(3-propylbenzothiazolin-2-ylidene)dipalladium(II), 2.16(b)

Complex 2.16(b) was prepared similarly to 2.13(a) from 2.2(b) (100 mg, 0.11 mmol)

and 1,2-bis(4-pyridyl) ethane (21 mg, 0.11 mmol) Yield: 79 mg (0.07 mmol, 65 %)

2.94 (s, 4H, CH 2 CH 2), 2.33 (m, 3JHH = 7.9 Hz, 4H, CH2CH 2CH3), 1.22 (t, 3JHH = 7.5

Hz, 6H, CH2CH2CH 3) 13C{1H} NMR (125 MHz, CDCl3): δ 193.2 (NSC), 152.7,

Pd(OAc)2 (225 mg, 1.00 mmol) Purification by column chromatography using

CH2Cl2 as eluant gave 2.17 as a red solid Slow evaporation of a concentrated CH2Cl2solution yielded red crystals suitable for X-ray diffraction studies Yield: 193 mg (0.18 mmol, 36%) 1H NMR (500 MHz, DMSO-d6): δ 8.24 (d, 3

Pyridine (5 mL) was added to complex 2.17 (602 mg, 0.06 mmol) and the mixture

was stirred at r.t overnight The clear yellow solution thus obtained was evaporated to

dryness under vacuum The solid product 2.18 was redissolved in CH2Cl2 onto which

was layered Et2O to give yellow single crystals upon standing Yield: 678 mg (0.11 mmol, 98%) 1H NMR (500 MHz, CDCl3): δ 9.06 (d, 3

CH(CH3)2), 19.2 (s, CH(CH3)2) MS (ESI, positive mode) m/z (%): 587 (100) [M – I]+

+ 3CH3OH Anal Calc for C15H16I2N2SPd (M = 616.59): C, 29.22; H, 2.62; N, 4.54;

S, 5.20 Found: C, 30.95; H, 2.66; N, 4.72; S, 5.64

trans-diiodo(3-isopropylbenzothiazolin-2-ylidene)(2-aminopyridine)palladium(II), 2.19

A mixture of 2.17 (110 mg, 0.10 mmol) and 2-aminopyridine (19 mg, 0.20 mmol)

was suspended in CH2Cl2 (5 mL) and stirred overnight at r.t Upon solvent evaporation under vacuum, the yellow solid was washed with Et2O several times Diffusion of Et2O into a concentrated CH2Cl2 solution yielded yellow crystals suitable for X-ray diffraction studies Yield: 101 mg (0.16 mmol, 80%) 1H NMR (500 MHz, CDCl3): δ 7.90 (d, 3

JHH = 8.2 Hz, 1H, 2-py-H), 7.78 (m, 1H, 3-py-H), 7.55-7.49 (m,

1H, Ar-H), 7.47-7.42 (m, 2H, Ar-H), 7.41-7.37 (m, 1H, Ar-H), 6.67 (m, 1H, 4-py-H), 6.59 (d, 3JHH = 8.2 Hz, 1H, 5-py-H), 6.54 (m, 3JHH = 7.3 Hz, 1H, CH(CH3)2), 5.38 (s

br, 2H, NH2), 1.94 (d, 3JHH = 7.6 Hz, 6H, CH(CH 3)2 13C{1H} NMR (125 MHz, CDCl3): δ 191.6 (s, NCS), 157.9, 149.7, 141.4, 138.5, 137.7, 126.1, 124.6, 122.4,

115.9, 114.1, 108.6 (s, py-C and Ar-C), 63.3 (s, CH(CH3)2), 19.4 (s, CH(CH3)2) MS

(ESI, positive mode) m/z (%): 504 (50) [M – I]+, 1042 (100) 2[M – I]+ + CH3OH

Anal Calc for C15H17I2N3SPd (M = 631.63): C, 28.52; H, 2.71; N, 6.65; S, 5.08 Found: C, 28.92; H, 2.69; N, 6.54; S, 5.06

124.6, 122.2, 115.9, 91.9 (s, py-C and Ar-C), 63.5 (s, CH(CH3)2), 19.2 (s, CH(CH3)2)

MS (ESI, positive mode) m/z (%): 583 (100) [M - I - CH3OH]+, 742 (50) [M + H]+ Anal Calc for C15H15I3N2SPd.CH2Cl2 (M = 827.42): C, 23.23; H, 2.07; N, 3.39; S, 3.88 Found: C, 22.72; H, 1.90; N, 3.38; S, 4.66

trans-diiodo(3-isopropylbenzothiazolin-2-ylidene)(4-tert-butyl-pyridine)palladium(II), 2.21

Complex 2.21 was prepared as a yellow solid similar to 2.19 from 2.17 (140 mg, 0.13

mmol) and 4-tert-butyl-pyridine (35 mg, 0.26 mmol) Yellow single crystals of 21

were obtained from a diffusion of Et2O into a concentrated CH2Cl2 solution Yield: 96

mg (0.14 mmol, 15%) 1H NMR (500 MHz, CDCl3): δ 8.93 (d, 3

JHH = 6.9 Hz, 2H, 2,

6-py-H), 7.89 (d, 3JHH = 8.2 Hz, 1H, Ar-H), 7.76 (d, 3JHH = 7.6 Hz, 1H, Ar-H), 7.44 (t,

3

JHH = 7.6 Hz, 1H, Ar-H), 7.37 (t, 3JHH = 7.6 Hz, 1H, Ar-H), 7.31 (d, 3JHH = 6.9 Hz,

2H, 3, 5-py-H), 6.58 (m, 3JHH = 7.1 Hz, 1H, CH(CH3)2), 1.92 (d, 3JHH = 7.0 Hz, 6H, CH(CH 3)2), 1.32 (S, 9H, (CH 3)3) 13C{1H} NMR (125 MHz, CDCl3): δ 189.9 (s, NCS), 162.4, 153.6, 149.6, 141.3, 138.9, 126.0, 124.5, 122.2, 121.8, 115.8 (s, py-C

and Ar-C), 63.3 (s, CH(CH3)2), 35.1 (CH3)3, 30.3 (CH3)3, 19.2 (s, CH(CH3)2) MS

(ESI, positive mode) m/z (%): 544 (20) [M - I]+, 819 (100) [M - I]+ +

2[tert-butyl-pyridine], 948 (80) [M - I]+ + 3[tert-butyl-pyridine] Anal Calc for C19H25I2N2SPd (M = 673.71): C, 33.87; H, 3.74; N, 4.16; S, 4.76 Found: C, 34.42; H, 3.50; N, 4.11;

S, 5.39

3.2.7 Synthesis of Complexes 2.22-2.27 (Chapter Two, Section 2.8)

Complex 2.22 was prepared from the reaction of the parent Pd(II) dinuclear complex

(97 mg, 0.09 mmol) and imidazole (13 mg, 0.18 mmol) The mixture was suspended

in CH2Cl2 (5 mL) and stirred overnight at room temperature The yellow precipitate thus obtained was washed several times with Et2O The yellow solid was obtained

Yellow single crystals of 2.22 were obtained from a diffusion of Et2O into a concentrated CH2Cl2 solution Yield: 97 mg (0.16 mmol, 89%) 1H NMR (500 MHz, CDCl3): δ 9.47 (s, 1H, NH), 8.41 (s, 1H, NCHN), 7.88 (d, 3

CH(CH3)2) MS (ESI, positive mode) m/z (%): 543 (100) [M - I]+ + 2CH3OH Anal Calc for C13H15I2N3SPd.Et2O.H2O (M = 697.71): C, 29.26; H, 3.90; N, 6.02; S, 4.60 Found: C, 29.06; H, 3.11; N, 5.61; S, 5.74

trans-diiodo(3-isopropylbenzothiazolin-2-ylidene)(1-(2,4,6-trimethyl-phenyl)-1H-imidazole -ĸN)Pd(II), 2.23

Complex 2.23 was prepared similarly to 2.22 from the parent Pd(II) dinuclear

complex (108 mg, 0.10 mmol) and 1-(2,4,6-trimethyl-phenyl)1H-imidazole (37 mg,

0.2 mmol) A yellow solid was obtained Yellow single crystals of 2.23 were obtained

from a diffusion of Et2O into a concentrated CH2Cl2 solution Yield: 97 mg (0.11 mmol, 55%) 1H NMR (500 MHz, CDCl3): δ 8.27 (s, 1H, NCHN), 7.89 (s, 1H, Ar-H), 7.88 (s, 1H, Ar-H), 7.75 (d, 3JHH = 8.2 Hz, 1H, Ar-H), 7.42 (t, 3JHH = 7.9 Hz, 1H, Ar-

H), 7.35 (t, 3JHH = 7.6 Hz, 1H, Ar-H), 6.97 (s, 2H, NCH=), 6.81 (s, 1H, Ar-H), 6.58

(m, 3JHH = 7.1 Hz, 1H, CH(CH3)2), 2.34 (s, 3H, CH3), 2.17 (s, 3H, CH3), 2.02 (s, 3H,

CH3), 1.91 (d, 3JHH = 7.6 Hz, 6H, CH(CH 3)2) 13C{1H} NMR (125 MHz, CDCl3): δ 190.3 (s, NCS), 143.5 (s, NCHN), 141.4, 139.6, 138.9, 135.1, 133.3, 132.5, 129.2,

125.9, 124.4, 122.1, 120.1, 115.8 (s, Ar-C), 63.1 (s, CH(CH3)2), 21.1 (s, CH3), 19.1 (s,

CH(CH3)2), 17.6 (s, CH3) MS (ESI, positive mode) m/z (%): 1136 (100) [M - I]+ + 2(C12H14N2) + CH3CN Anal Calc for C22H25I2N3SPd.Et2O.CH2Cl2 (M = 882.80): C, 36.73; H, 4.22; N, 4.76; S, 3.63 Found: C, 36.92; H, 4.72; N, 4.59; S, 3.92

Complex 2.24 was prepared similarly to 2.22 from the parent Pd(II) dinuclear

complex (100 mg, 0.09 mmol) and benzimidazole (22 mg, 0.19 mmol) A yellow

solid was obtained Yellow single crystals of 2.24 were obtained from a diffusion of