Reactions of Diethylazo-Dicarboxylate with Frustrated Lewis Pairs

Abstract

Reactions of PAr3/B(C6F5)3 (Ar=o-Tol, Mes, Ph) FLPs with diethyl azodicarboxylate (DEAD) afford the corresponding FLP addition products 1–3 in which P−N and B−O linkages are formed. In contrast, the reaction of BPh3, PPh3 and DEAD gave product 4 where P−N and N−B linkages were confirmed. In all cases, other binding modes were computed to be both higher in energy and readily distinguishable by 31P and 11B NMR parameters. These data illustrate the influence of steric demands and electronic structures on the nature of the products of FLP reactions with DEAD.