Acid Azide as an Acylating Agent. I.
Shigehiko Sugasawa, Hiroshi Tomisawa · Pharmaceutical Bulletin · 1955
Diethyl sodiomalonate and ethyl sodioacetoacetate were treated with azides of α-, β-, and γ-pyridine-carboxylic acids in absolute ether, furnishing the corresponding diethyl pyridoylmalonate and ethyl pyridoylacetoacetate in fair yields. Thus, azide of various basic carboxylic acids can advantageously be used for similar purposes, when acid chloride is hard to obtain in a pure state, which is usually the case in various basic carboxylic acid.