o-(.alpha.-Benzotriazolylalkyl)phenols: Novel Precursors for the Preparation of 1,1-Bis(2-hydroxyaryl)alkanes
摘要:
Reactions of o-(alpha-benzotriazolylalkyl)phenols with a variety of substituted phenols and naphthols in the presence of a base provide efficient access to symmetrical and more importantly to unsymmetrical 1,1-bis(2-hydroxyaryl)alkanes.
A metal-free C(sp(3))-H/N-H cross-coupling of azoles with xanthenes and related activated arylmethylenes is presented. Both the use of azoles and the activation pattern of C(sp(3))-H sources are essential for this transformation. In the presence of 2.0 equiv of benzoyl peroxide (BPO), methylenes bearing a heteroatom-bridged bisaryl group reacted with various azolic N-H sources to afford C-N bond forming products in usually excellent or quantitative yields, and the diphenylmethane and methylenes coactivated by a phenyl group and an adjacent heteroatom are less reactive. Mechanistic investigations suggest that a radical/radical cross-coupling pathway might be involved.[GRAPHICS].
Katritzky, Alan R.; Lan, Xiangfu; Lam, Jamshed N., Chemische Berichte, 1991, vol. 124, # 8, p. 1809 - 1817
作者:Katritzky, Alan R.、Lan, Xiangfu、Lam, Jamshed N.