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

Figure S51. 13 C{ 1 H} NMR.
Synthesis of trans-[(PPh 3)(Ph 2P(CH 2) 2B(C 8H 14))Re(<strong>CO</strong>) 4][OTf] ([1-E 1Ph 1][OTf]).
Under the nitrogen atmosphere of a glovebox a 20 mL scintillation vial was charged with 819 mg
(1.19 mmol) trans-(PPh 3)Re(<strong>CO</strong>) 4I and 10 mL CH 2Cl 2. Solid AgOTf (382 mg, 1.49 mmol, 1.25
equiv) was added, and the reaction mixture was stirred for 2 hours with protection from light.
The resulting cloudy mixture was filtered through celite to give a clear, pale yellow solution. A
100 mL Teflon-stoppered pressure tube was charged with the filtrate, and a solution of 398 mg
(1.19 mmol) Ph 2P(CH 2) 2B(C 8H 14) in 5 mL CH 2Cl 2 was added, along with a stirbar. The tube was
sealed, removed from the glovebox, and heated in an oil bath to 60 °C for 24 hours. After the
allotted time, the reaction was cooled to ambient temperature and returned to the box. The
reaction mixture was filtered and the solvent were removed in vacuo, giving 1.21 g (1.15 mmol,
97%) pure white [1-E 1Ph 1][OTf]. 1 H NMR (CD 2Cl 2, 500 Mhz): δ 1.10-1.18 (m, 2H), 1.34 (dd, J
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