Organolutetium-Mediated Dearomatization and Functionalization of Pyrimidine Rings

The synthesis of a pentadentate NNNNN bis(phosphinimine)carbazole pincer ligand bearing two pyrimidine N-aryl rings is reported. A dialkyl lutetium complex of the ligand, prepared by alkane elimination with Lu-(CH2SiMe3)(3)(THF)(2), was found to undergo an unusual transformation involving a double alkyl shift whereby the -CH2SiMe3 groups on the metal migrated to both pyrimidine rings. This migration afforded a final product that featured alkyl-functionalized, dearomatized ligand pyrimidine rings.