Reactivity of [Ce(NR₂)₃] (R = SiMe₃) with Prospective Carbon Atom Transfer Reagents

Abstract

Herein, we report the synthesis, characterization, and reactivity of the N-(isocyanoimine)triphenylphosphine (CNNPPh3) and bis(diisopropylamino)cyclopropenylidene (BAC) adducts of [Ce(NR2)3] (R = SiMe3): namely, [(NR2)3Ce(CNNPPh3)] (1) and [(NR2)3Ce(BAC)] (2), respectively. Photolysis of 1 with a 380 nm LED source for 1 month results in clean formation of [(NR2)3Ce(NCNPPh3)] (3), via reorganization of the nitrilimine ligand to its carbodiimide isomer. Photolysis of 2 with a 365 nm LED source results in formation of the methylenecyclopropene species [(iPr2N)2C3C(NiPr2)(CCNiPr2)] (5) via the formal dimerization and rearrangement of two BAC fragments. Compound 5 can also be generated under catalytic conditions by performing the photolysis of BAC in the presence of 10 mol % of [Ce(NR2)3].