Ferrocene Compounds. XXIX.* Efficient Syntheses of 1’-Aminoferrocene-1-carboxylic Acid Derivatives

Sa？etak The syntheses of 1'-aminoferrocene-1-carboxylic acid (2a) and its derivatives are reported. Reaction of 1'-methoxycarbonylferrocene-1-carboxylic acid with ethyl chloroformate / triethylamine / sodium azide gave methyl 1'-azidocarbonylferrocene-1-carboxylate (4), which was rearranged in acetic anhydride and hydrolyzed into N-acetyl derivative of 2a. Azide 4 was converted into the corresponding benzyl carbamate 7, which was hydrolyzed into acid-carbamate 9 and hydrogenated into amino acid 2a. The crucial in-termediate 4 was transformed into tert-butyl carbamate 10 and hydrolyzed into N-Boc-2a