Synthesis of Seven-Membered Carbocyclic Rings via a Microwave-Assisted Tandem Oxyanionic 5-exo dig Cyclization-Claisen Rearrangement Process

摘要

Appropriately substituted l-alkenyl-4-pentyn-l-ol systems,readily prepared from simple starting materials,serve as useful precursors to a number of substituted cyclohept-4-enone derivatives via a microwave-assisted tandem oxyanionic 5-exo cyclization/Claisen rearrangement sequence.The reactions involving terminally substituted 4-pentyn-1-ols were found to be highly stereoselective,with the a and beta groups in the final product showing a strong preference for the trans orientation.