Synthesis of Polyfunctionalized Triaryllanthanum Reagents by Using Ph₃La and Related Species as Exchange Reagents

Abstract

Ph₃ La⋅5 LiCl and the related (m-xylyl)₃ La⋅5 LiCl were used as Hal/La exchange reagents (Hal=Br, I) for the preparation of various triaryl- and triheteroaryl-lanthanum derivatives. These new exchange reagents are compatible with isoquinolines and some functional groups such as a nitrile or an ester. The reactivity of the resulting lanthanum compounds towards electrophiles, such as ketones, aldehydes, N,N-dimethylamides, and primary alkyl halides was investigated. Additionally, a Pd-catalyzed cross-coupling procedure with aryl bromides was developed.