The Dakin-West Reaction of N-Acyl-1,2,3,4-tetrahydroisoquinoline-1-carboxylic Acids Using Trifluoroacetic Anhydride: Structural Revision for the Unexpected Product
作者:Masami Kawase、Youichi Okada、Hiroshi Miyamae
DOI:10.3987/com-97-8053
日期:——
The Dakin-West reaction of N-pivaloyl- and N-benzoyl-1,2,3,4-tetrahydroisoquinoline-1-carboxylic acids (1 a-e) with trifluoroacetic anhydride yielded unexpectedly 1-(1-acyloxy-2,2,2-trifluoroethyl)-3,4-dihydroisoquinoline derivatives (3a-e) in good yields. Among of the products (3), the structure of 3 b has been confirmed by X-Ray crystallography. The carbamate derivatives (1h, i) gave 1-trifluoroacetyl-N-acyl-1,2,3,4-tetrahydroisoquinolines (4e, f), the Dakin-West reaction products, as a main product. The reaction of N-acetyl derivative (1 g) produced completely different type of the product (5).