摘要:
A general method based on the sequential reactivities of bis-bromocycloalkenes (3-5) is proposed for the preparation of phosphonocycloalkanes (1a/b-3a/b), representing structural constrained analogues of AP4. For the synthesis,of an additional congested AP4 analogue (4), an intramolecular cyclopropanation of a ketocarbene towards a vinyphoshonate, assisted by Rh(OAc)(2) was successfully experimented. (C) 2002 Published by Elsevier Science Ltd.