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Zaidlewicz, M.; Pakulski, M. M., Science of Synthesis: Stereoselective Synthesis, (2011) 2, 95.
Early organocatalytic asymmetric hydrosilylations of prochiral ketones, catalyzed by chiral Lewis bases, proceeded with low to moderate selectivity.[202–205] A more recently developed chiral 5-phenyloxazole derivative, N-formyl pipecolinic acid amide, and N-formyl-α′-(2,4,6-triethylphenyl)-(S)-proline (59) are all more selective.[171,206,207] The catalyst 59 is highly selective in the reduction of alkyl aryl ketones with trichlorosilane, producing the corresponding alcohols in up to 99.7% ee. Thus, acetophenone, 1-phenylpropan-1-one, and 1-phenylbutan-1-one, as well as ring-substituted acetophenones afford products of 93–97% ee (Scheme 43).
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References
[171] | Meee, M.; Meee, M.; Mee, M.; Mee, M., Meee. Meeeee. (Meeeeeeee), (8888), 8888. |
[202] | Meee, M. M.; Meeeeeee, M. M.; Meeeee, M.; Meeeee, M. M., Meeeeeeeeee Meee., (8888) 88, 8888. |
[203] | Meeeeeeee, M.; Meeee, M. M., Meeeeee, (8888), 8888. |
[204] | MeMeeee, M. M.; Meeee, M. M., Meeeeeeeeee Meee., (8888) 88, 8888. |
[205] | Meeeeee, M.; Meeeeee, M.; Meeeeee, M.; Meeeeeeee, M.; Meee, M.; Meeeeeeee, M., Meeeeeeeeee Meee., (8888) 88, 8888. |
[206] | Meeeee, M. M.; Meeeee, M. M. M. M.; Meeíeee-Móeee, M.; Meeeeeá, M.; Meeee, M.; Mečeeeeý, M., Meeee. Meee., (8888) 888, 8888; Meeee. Meee. Mee. Me., (8888) 88, 8888. |
[207] | Meeeeeeee, M.; Meeee, M.; Meeeee, M.; Meeeeee, M.; Meeeeee, M., Mee. Meee., (8888) 8, 8888. |
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- 8.Meeeee-Meee, (8888) M 88e8, 888.