作者:David Tilly、Subhendu S Samanta、Ferenc Faigl、Jacques Mortier
DOI:10.1016/s0040-4039(02)01976-7
日期:2002.11
ortho-Substituted-2-biphenyl carboxylic acids of the type 3a–j were prepared by the tandem metalation sequence from 2-biphenyl carboxylic acid 1 with sec-butyllithium in THF at −78°C followed by quenching with electrophiles. The carboxylic acids 3a–f were converted into 1-substituted fluorenones 4a–f upon treatment with methanesulfonic acid.
Contribution to the Study of the Mechanism of Directed Remote-Metalation. Evidence for the Intermediacy of a Geminal Dimetallo Dialkoxide C(OM)<sub>2</sub> (M = Li, K), First Doubly Charged Director of Ortho Metalation
作者:David Tilly、Subhendu S. Samanta、Asish De、Anne-Sophie Castanet、Jacques Mortier
DOI:10.1021/ol0474709
日期:2005.3.1
mechanism of the metalation of 2-biphenyl carboxylic acid (1) with the Lochmann-Schlosser superbase was determined by deuteriolysis. Both ortho (C(3)) and remote (C(2')) positions are metalated. The C(2')-metalated species 2 cyclizes instantaneously. Under suitable conditions, the doubly charged geminal dimetallo dialkoxide group C(OM)(2) 4 directsmetalation in the adjacent position (C(1)), affording