LH-Phosphirenes

Gonbeau D, Pfister-Guillouzo G, Marinetti A, Mathey F (1985) Calculations predict that complexation of the a3-phosphorus atom strongly stabilizes lH-phosphirenes. Inorg Chem 24 4133... 

A similar situation is found in the lH-phosphirenes a) Marinetti A, Mathey F, Fischer J, Mitschler A (1984) J Chem Soc Chem Commun 45 b) Wagner O, Ehle M, Birkel M, Hoffmann J, Regitz M (1991) Chem Ber 124 1207... 

A study of the reactivity of l-chloro-lH-phosphirenes 342 with nucleophiles has shown that the chlorine is easily replaced. Ab initio calculations suggest that IH-phosphirenes invert their configuration at phosphorus by a rotation of the PX group above the C2 moiety, rather than by the more usual trigonal inversion pathway involving a C2v-transition state. Related calculations on the aromaticity of IH-phosphirenium cations 343 have shown that the a ABMO associated with the P-X bond acts like an empty p-orbital. A facile route to the phosphirenium salts 344 is afforded by the reaction of the phosphiranium salt 345 with alkynes. The P -azaphosphirene system 346 has been obtained from the reaction of an iminophosphene with terminal alkynes. ... 

The addition of monochlorocarbenes to phospha-alkynes results initially in the formation of the transient 2H-phosphirenes (231), which then undergo rearrangement, with migration of chlorine from carbon to phosphorus, to give the stable P-halo-lH-phosphirenes (232). Unlike their nitrogen analogues, the latter cannot... 

The reactions of P-halophospha-alkenes with carbenes provide a new route to 1-chloro-lH-phosphirines (181). Such compounds are highly reactive, and a study of nucleophilic displacement reactions at phosphorus has been facilitated by preparation of the related P-W(CO)5 complexes.The first pentacoordinate systems derived from phosphirenes, (182), have been formed in the reactions of P-halo- or P-cyano-phosphirenes with tetrachloro-o-quinone. Evidence has been presented for the rearrangement of P-chlorophosphirenium ions (183) to the vinylphosphenium ions (184)... 

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