Ambident Reactivity of P˭CH‒N‒Heterocycles: Lithiation and Substitution Sites
作者:Joachim Heinicke、Bhaskar R. Aluri、Basit Niaz、Sebastian Burck、Dietrich Gudat、Mark Niemeyer、Oldamur Holloczki、Laszlo Nyulaszi、Peter G. Jones
DOI:10.1080/10426507.2010.514486
日期:2011.3.31
Benzofused 1H-1,3-azaphospholes are lithiated at the N-atom by tBuLi but phosphinylation takes place at either the N- or the P-atom. Smaller chlorophosphines react at nitrogen, bulkier react at phosphorus. Substituents at C2 promote the latter mode. N- Substituted 2H-1,3-benzazaphospholes undergo CH-metalation or addition at the P=C bond, depending on the conditions, and allow access to 2-functionally substituted benzazaphospholes or their 2,3-dihydro derivatives, new sigma P-2,X or sigma P-3,X hybrid ligands (X=O,P).
Ambident PCN Heterocycles: N- and P-Phosphanylation of Lithium 1,3-Benzazaphospholides
Synthetic and structural aspects of the phosphanylation of 1,3‐benzazaphospholides 1Li, ambident benzofused azaphosphacyclopentadienides, are presented. The unusual properties of phospholyl‐1,3,2‐diazaphospholes inspired us to study the coupling of 1Li with chlorodiazaphospholene 2, which led to the N‐substituted product 3. Reaction of 1Li with chlorodiphenyl‐ and chlorodicyclohexylphosphane likewise