Affordable Access

Publisher Website

Tandem intramolecular carbolithiation–transmetallation: from lithium to copper or boron chemistry

Authors
Journal
Tetrahedron
0040-4020
Publisher
Elsevier
Publication Date
Volume
61
Issue
7
Identifiers
DOI: 10.1016/j.tet.2004.12.047
Keywords
  • Lithium–Copper Transmetallation
  • Sn2′ Reaction
  • Acylation
  • Michael Addition
  • Lithium–Boron Transmetallation
  • Suzuki–Miyaura Coupling

Abstract

Abstract Lithium/copper transmetallation from the organolithium intermediate 3 (obtained via intramolecular carbolithiation of the acyclic organolithium 2 , generated by a chlorine–lithium exchange) gives the corresponding organocopper intermediate 5 . This intermediate reacts with eletrophiles, such as allylic or propargylic halides, acyl chlorides or α,β-unsaturated carbonyl compounds giving the expected compounds 6– 10 , which are not possible to be obtained directly from the organolithium 3 . On the other hand, lithium/boron transmetallation affords the corresponding alkylboronic acid 11 which, after palladium-catalysed Suzuki–Miyaura cross-coupling reaction with different aryl bromides gives the expected products 12 with modest yields, the corresponding Ullman biarylic homocoupling products being the major by-products.

There are no comments yet on this publication. Be the first to share your thoughts.