Homogeneous CO Hydrogenation: Ligand Effects on the Lewis Acid ...

Reaction of [Na][(PPh 3)(Ph 2P(CH 2) 2B(C 8H 14))Re(<strong>CO</strong>) 2(C(O)CH 2O—)] with MeOTf.
A 20 mL scintillation vial was charged with 55.3 mg (0.0485 mmol) [Na(THF) 3][3-E 1Ph 1] and 2
mL C 6H 5Cl. With stirring, 5.5 µL (0.0485 mmol) MeOTf was added by syringe. The reaction
was stirred overnight (NMR studies show reaction to be complete in as little as 30 minutes,
however), at which time it was filtered, washed with C 6H 6, and the solvent removed from the
filtrate under vacuum, affording 33 mg (0.0362 mmol, 75%) 13 as a yellow powder. Single
crystals (large yellow blocks) were grown from vapor diffusion of pentane into a C 6H 5Cl (or
C 6H 6) solution of 12. 1 H NMR (C 6D 6, 500 MHz): δ 1.00 (br, 1H, Ph 2PCH 2CH 2B(C 8H 14)), 1.24
(m, 1H Ph 2PCH 2CH 2B(C 8H 14)), 1.31 (br, 1H, Ph 2PCH 2CH 2B(C 8H 14)), 1.66-1.77 (m, 1H,
Ph 2PCH 2CH 2B(C 8H 14)), 1.96-2.47 (m, 12H, Ph 2PCH 2CH 2B(C 8H 14)), 2.74 (m, 1H,
Ph 2PCH 2CH 2B(C 8H 14)), 2.80 (3H, Re=C(OCH 3)CH 2O-), 3.30 (m, 1H, Ph 2PCH 2CH 2B(C 8H 14)),
6.8-6.9 (m, 2H, Ph 2PCH 2CH 2B(C 8H 14)), 6.99 (m, 4H, Ph 2PCH 2CH 2B(C 8H 14)), 7.08 (m, 9H,
PPh 3), 7.65 (m, 2H, Ph 2PCH 2CH 2B(C 8H 14)), 7.71 (m, 6H, PPh 3), 7.84 (m, 2H,
Ph 2PCH 2CH 2B(C 8H 14)). 31 P{ 1 H} NMR (C 6D 6, 202 MHz): δ 5.7 (d, 2 J PP = 114.2 Hz, 1P), 13.5 (d,
2 JPP = 114.3 Hz, 1P). 13 C{ 1 H} NMR (C 6D 6, 126 MHz): δ 15.00 (br), 24.39 (br), 24.90 (br), 26.06
(Ph 2PCH 2CH 2B(C 8H 14)), 26.51 (Ph 2PCH 2CH 2B(C 8H 14)), 27.96 (d, J PC = 26.1 Hz,
Ph 2PCH 2CH 2B(C 8H 14)), 32.00 (Ph 2PCH 2CH 2B(C 8H 14)), 32.25 (Ph 2PCH 2CH 2B(C 8H 14)), 34.05
(Ph 2PCH 2CH 2B(C 8H 14)), 34.51 (Ph 2PCH 2CH 2B(C 8H 14)), 66.55 (Re=C(OCH 3)CH 2O-), 90.99
(Re=C(OCH 3)CH 2O-), 128.55 (d, JPC = 9.1 Hz, m-Ph 2PCH 2CH 2B(C 8H 14)), 128.74 (d, J PC = 9.7
Hz, m-PPh 3), 130.36 (p-PPh 3), 130.79 (d, J PC = 8.7 Hz, p-Ph 2PCH 2CH 2B(C 8H 14)), 133.72 (d, J PC
= 9.2 Hz, o-Ph 2PCH 2CH 2B(C 8H 14)), 133.86 (d, J PC = 10.7 Hz, o-PPh 3), 136.73 (d, J PC = 45.2 Hz,
ipso-PPh 3), 144.75 (d, J PC = 46.6 Hz, ipso-Ph 2PCH 2CH 2B(C 8H 14)), 203.43 (br t, J PC ~ 7.9 Hz,
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