Novel cations and molecules from phosphaalkynes, 1H-phosphirenes and from tetraphosphacubane

Generation and trapping (counter ion) of the phosphavinyl cation (the P-ana log of vinyl cation) by low temperature protonation of kinetically stable p hosphaalkynes in super acid media led to the formation of the corresponding phosphaalkenes without direct observation of a long-lived cation. Reaction s of RCP (R = tBu, I-Ad) with "PhSeF" and with PhSeCl resulted in bis-pheny lselenenylation and chlorophenylselenenylation respectively, forming novel Se-containing phosphaalkenes. Ionization of 1-H-triflato-phosphirene with B (OTf) (3) /SO2 led to the direct observation of a persistent phosphirenyliu m cation. The (CO)(5) W-complexed phosphirenylium cation was subsequently g enerated from the (CO)(5) W-complexed triflate and trifluoroacetate derivat ives. Progress in P-functionalization of tetraphosphacubane by reactions wi th potent electrophiles (i.e. MeOTf, EtOTf"PhCH2OTf", TMSCH2OTf), alkynyl-i odonium triflates and with protic superacids are briefly summarized.