ORGANOPHOSPHORUS COMPOUNDS WITH TERTIARY ALKYL SUBSTITUENTS .5. SYNTHESIS AND REACTIONS OF TRIPHENYLMETHYL-SUBSTITUTED DIHALOPHOSPHINES TRTPX(2) (TRT=TRIPHENYLMETHYL-, X=F,CL, BR) - X-RAY-CRYSTAL STRUCTURES OF TRIPHENYLMETHYL DICHLOROPHOSPHINE TRTPCL

摘要

The dihalophosphines TrtPX(2) (X = Cl:2, Br:3) were obtained in the reaction of TrtP(:O)(H)OH 1 with PCl3 and PBr3, respectively. 2 could also be synthesized from TrtMgCl and PCL(3), 3 from 2/Me(3)SiBr. TrtPF(2) 4 was prepared by the fluorination of 2 with NaF or from TrtLi/PF2Cl. The reduction of 2 with LiAlH4 or HSiCl3/NaOH(aq) yielded TrtPH(2) 6, the reaction with NaF/H2O led to TrtP(:O)(H)F 9. (TrtPCl(2))(2)Mo(CO)(4) 10 was observed in the system 2/(NOR)Mo(CO)(4) by P-31-NMR-spektroscopy. 4 was oxidized with TrtN(3) or sulfur to give the lambda(4)P(V)-compounds TrtP(:NTrt)F-2 11 and TrtP(:S)F-2 12 respectively. Whereas the oxidation of 4 and (1)BuPF(2) with tetrachloro-o-benzoquinone (TOB) led to the corresponding difluorophosphoranes 13 and 14, no reaction could be observed when 4 was treated with hexafluoroacetone (HFA) at elevated temperatures. In a fashion typical of difluorophosphines, 4 reacted with (COD)MCl(2) (M = Pd, Pt) or (NOR)Mo(CO)(4) to give the co-ordination compounds 15, 16 and 18a. Upon heating cis(TrtPF(2))(2)Mo(CO)(4) 18a isomerized to give the thermodynamically favoured trans-complex 18 b. The reaction of 4 with Fe-3(CO)(1) led to (TrtPF(2))Fe(CO)(4) 17 as the only phosphorus-containing product, instead of the phosphinidene complex TrtP(mu-F)(2)Fe-3(CO)(9). X-ray structure analyses of compounds 2 and 12 were carried out. The P-C bond in 2 is unusually long (193.3 pm). The F-P-F angle in 12 is narrow (98.14 degrees). [References: 59]