Process for the production of 4-substituted azetidinone derivative

摘要

The present invention provides a process for the production of a 4-substituted azetidinone. The process comprises reacting <IMAGE> (III) wherein R represents a hydrogen atom or a protecting group for N, R1 represents an alkyl which may be a substituent having an unprotected or protected hydroxyl group; and Z represents a leaving group; with represents hydrogen or alkyl, R3 and R4 each represent hydrogen, alkyl, alkenyl, alkynyl, phenyl, cycloalkyl, or naphthyl, or R3 and R4, together with the carbon atom to which they are bonded, form a ring system; X and Y each represent oxygen, sulfur or N-r1, wherein r1 represents a hydrogen atom or lower alkyl; A, B, D and E each represent nitrogen or C-r2, wherein r2 represents hydrogen, halogen, lower alkyl or lower alkoxy, provided that at least two of A, B, D and E are C-r2; and a ring involving G, J and K has two carbon/carbon double bonds therein and one of G, J and K represents oxygen, sulfur or N-r1 while the remaining two represent C-r2; in the presence ofM(Hal)n(R5)m(V)wherein M represents a metal atom; Hal represents halogen; R5 represents lower alkyl, lower alkoxy, phenoxy, substituted phenoxy or cyclopentadienyl; and n and m are each 0, 1, 2, 3, 4 or 5, provided that n+m stands for the valence of M; and a base to thereby give: <IMAGE> (II-1) or <IMAGE> (II-2)