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

(0.0264 mmol) solid [1-E 2][BF 4], and the reaction mixture returned to the NMR tube. After 30
minutes, an equilibrium mixture of all the constituents was achieved ([1-E 2] + , 2-E 2, [1-P 2] + , and
2-P 2). The spectra were essentially the same as in the preceding reaction, with K eq again roughly
1 ( 31 P NMR integration). The equilibrium mixture was stable for at least 3.5 hours.
Figure S122. 31 P{ 1 H} NMR.
Reaction of 2-E 2 with [1-Ph 2][BAr F
4].
A vial was charged with 25.2 mg (0.0239 mmol) [1-E 2][BF 4] and ~0.6 mL C 6D 5Cl. With stirring,
15.3 mg (0.0239 mmol) [HPt][PF 6] was added as a solid, partwise. The colorless solution turned
yellow with precipitation and was stirred for ~10 min, after which time the reaction mixture was
added to 40.3 mg (0.0239 mmol) solid [1-Ph 2][BAr F
4]. NMR spectroscopy revealed a mixture of
all the possible constituents, in roughly equal parts, with a estimated K eq ~ 1. As in the case of 2-
P 2, 2-Ph 2 showed shifted resonances in the 1 H NMR (Re-CHO) and 31 P NMR, with the 31 P NMR
S109