Preparation of Polyfunctional Biaryl Derivatives by Cyclolanthanation of 2‐Bromobiaryls and Heterocyclic Analogues Using nBu2LaCl⋅4 LiCl

Various aryl‐ and heteroaryl‐substituted 2‐bromobiaryls are converted to cyclometalated lanthanum intermediates by reaction with nBu₂LaCl?4 LiCl. These resulting lanthanum heterocycles are key intermediates for the facile preparation of functionalized 2,2′‐diiodobiaryls, silafluorenes, fluoren‐9‐ones, phenanthrenes, and their related heterocyclic analogues. X‐ray absorption fine structure (XAFS) spectroscopy was used to rationalize the proposed structures of the involved organolanthanum species.