Science of Synthesis

Liu, L.; Wang, D.; Li, C. -J., Science of Synthesis: Stereoselective Synthesis, (2011) 2, 603.

The reaction of silyl ketene acetal ‌67‌ with aldehydes promoted by chiral zirconium(IV) catalyst ‌26‌ preferentially affords anti-aldol adducts (e.g., ‌68‌) independent of the silyl enolate geometry (‌Scheme 29‌).[‌28‌] A small amount of water has also been found to be essential to obtain high selectivities. A 100-gram scale production of anti-(2S,3S)-3-[4-(benzyloxy)-3-chlorophenyl]-N-(trifluoroacetyl)-l-serine methyl ester, a key building block of the antibacterial vancomycin, has been reported based on the zirconium-catalyzed asymmetric Mukaiyama aldol reaction.[‌58‌]

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References