Addition of Benzodioxahalogenophosphoranes to the Carbonyl Group: New Phosphoranes and their Reactivity

Abstract

Halogenophosphoranes catPX₃ (X = C1, Br) (3), catPBr₂Y Y = CHF₂CF₂CH₂(4), F(5), OCH=CBr₂ (6), CN (7), cat = C₆H₄O₂-o] react with aldehydes containing electron-withdrawing groups (CZ₃CHO, Z = C1, Br) in solvent to form the products of insertion in P-X bond. The structure of compounds (12–15) and their diastereomeric composition were determined by the NMR ¹H, ¹³C, and ³¹P spectroscopy. Phosphoranes (8–11) disproportionate to PX₃ and cat₂POCHXCZ₃ (X, 2 = Br, Br; C1, Br) (16, 17). Dibromophosphoranes (4–7) and monobromophosphorane (3) are also added to the carbonyl group of CZ₃CHO to form unsymmetric P(V) derivatives catPBr(OCHBrCZ₃)Y (18, 19) and (16, 17, 20–25). The thermal behaviour of compounds (18, 19) was investigated.