New aryl-alkyl di:bromo-phosphane(s) and aryl-alkyl organyl bromo-phosphane(s)

摘要

Arylalkyl(dibromo)phosphanes (IA) of formula (I) and arylalkyl(organyl)(bromo)phosphanes (IIA) of formula (II) are new; ArCR1R2PBr2 (I); ArCR3R4(R5)PBr (II); in which Ar = phenyl, optionally mono- or poly-substituted by halogen, methoxy or tert.-butyl; R1, R2 = phenyl, mono- or poly-halo-phenyl, alkyl, mono-or poly-fluoro- or -chloro-alkyl or hydrogen (H); R3, R4 = phenyl, mono- or poly-halo-phenyl, alkyl, mono- or poly-halo-alkyl or H; R5 = phenyl, methyl, ethyl, tert.-butyl, cyclohexyl or benzyl. (I) in which R1 = R2 = H and dibenzyl(bromo)phosphane (a compound II) are excluded. Also claimed are methods of preparing compounds of formula (I) and (II) with a wider range of substituents as follows: (a) (I; Ar = phenyl or substituted phenyl; R1, R2 = phenyl, substituted phenyl, alkyl, haloalkyl or H, except R1 = R2 = H), and (b) (II; Ar = phenyl or substituted phenyl; R3, R4 = phenyl, substituted phenyl, alkyl, haloalkyl or H; R5 = phenyl, methyl, ethyl, tert.-butyl, cyclohexyl or benzyl), are prepared by reacting the corresponding alpha -substituted toluene derivatives with (a) phosphorus tribromide (PBr3) or (b) organyldibromophosphanes of the formula R5PBr2 respectively. Both reactions are carried out under ultra-violet (UV) light and preferably in the liquid phase at a temperature between 50 deg C and the b.pt. of the reaction mixture and with exclusion of atmospheric oxygen.