New acyl anionequivalents bearing a hydroxyl group at the β-position have been developed. Treatment of 3-benzyloxy-1-isocyanopropenes with lithium diisopropylamide (LDA) in THF at −78 °C generated the 1-lithio compounds, which reacted with alkyl halides to afford the corresponding 1-alkylated products in good yields. Acid hydrolysis of these alkylated products followed by hydrogenolysis of the resulting
The title amino acid derivatives have been prepared in two steps from 3-alkoxy-1-isocyanopropenes. The key step is the alkoxycarbonylation of 3-alkoxy-1-isocyano-1-lithiopropenes with alkyl chloroformates to afford the corresponding 4-alkoxy-2-isocyano-3-butenoates, which are readily converted to the title compounds by acidic hydrolysis.