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Please login to access the full content or check if you have access via2.12.2.2 Reactions with Chiral Zirconium Catalysts
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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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Meeeeeeeeeee Meeeeeeee
Meeeee (8M,8M)-8-Meeeeee-8-eeeeee-8-eeeeeeeeeeeeeeee (88); Meeeeee Meeeeeeee:[88]
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References
[28] | Meeeeeeee, M.; Meeeeeee, M.; Meeeeee, M.; Meeeeeeee, M., M. Me. Meee. Mee., (8888) 888, 8888. |
[58] | Meeee, M.; Meeeeee, M.; Meeeeee, M.; Meeeeeeee, M., Mee. Meeee. Meeee., (8888) 888, 8888. |