Catalytic asymmetric synthesis of ethyl (1R,2S)-dehydrocoronamate
摘要:
A synthesis of (1R,2S)-dehydrocoronamic acid ethyl ester was developed employing a regio- and enantioselective palladium-catalysed nucleophilic ring-opening of 3,4-epoxy-1-butene with a glycine anion equivalent as the key enantiodifferentiating step. The desired selectivity was achieved using Trost's naphthyl ligand. The subsequent activation of the free hydroxyl group and ring-closure by intramolecular S(N)2 reaction gave the desired amino acid ethyl ester. (c) 2006 Elsevier Ltd. All rights reserved.
Catalytic asymmetric synthesis of ethyl (1R,2S)-dehydrocoronamate
摘要:
A synthesis of (1R,2S)-dehydrocoronamic acid ethyl ester was developed employing a regio- and enantioselective palladium-catalysed nucleophilic ring-opening of 3,4-epoxy-1-butene with a glycine anion equivalent as the key enantiodifferentiating step. The desired selectivity was achieved using Trost's naphthyl ligand. The subsequent activation of the free hydroxyl group and ring-closure by intramolecular S(N)2 reaction gave the desired amino acid ethyl ester. (c) 2006 Elsevier Ltd. All rights reserved.