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

Figure S89. 1 H- 13 C gHMBC.
Reaction of 2-E 2 with H 2O.
Carbene 2-E 2 was prepared in the usual manner by dropwise addition of 21.8 μL (0.0218 mmol)
NaHBEt 3 (1.0 M in toluene) to a rapidly stirring C 6D 5Cl solution of 23.0 mg (0.0218 mmol)
cation [1-E 2] + . 1 H and 31 P{ 1 H} NMR studies showed clean formation of the carbene. 30 minutes
after preparation, 0.4 μL (0.0218 mmol) degassed deionized H 2O was added by syringe. After
addition, the solution immediately began bubbling, the yellow color of the carbene bleached, and
some precipitates formed. A 31 P{ 1 H} NMR experiment showed one prominent singlet at δ 1.4, in
a similar location as the cation [1-E 2] + (δ 0.3), along with minor impurities. The 1 H NMR
spectrum showed complete consumption of the carbene resonance at δ 13.96, and a conspicuous
resonance for H 2 gas at δ 4.49. The rest of the spectrum was rather broad and non-descript, but
matched the spectrum of crystals of 8 obtained from a separate reaction of carbene 2-E 2 with wet
<strong>CO</strong>.
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