Constructing chiral diazoacetoacetates by enantioselective catalytic Mukaiyama aldol reactions

Asymmetric catalysis of Mukaiyama aldol addition reactions of methyl 3-TMSO-2-diazo-3-butenoate 4 with aromatic aldehydes using AgF/(R)-BINAP at −20 °C produces chiral diazoacetoacetates in high chemical yields and with high enantiocontrol.

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Methyl 5-(p-chlorophenyl)-2-diazo-5-hydroxy-3-oxopentanoateC12H11ClN2O4Ee = 92%[α]D24.3=-63.6 (c 0.506, CH2Cl2)Source of chirality: asymmetric Mukaiyama aldol additionAbsolute configuration: (S) tentatively