Phosphinocarbenes synthesis

In this review, we present successively the theoretical aspect, the synthesis, the structural features, the reactivity, and lastly, the ligand properties of phosphinocarbenes. 

The next goal became obvious the synthesis of a phosphinocarbene 13. Diazo derivatives are classical precursors of carbenes. However, although... 

Thus, in 1988, we published a full paper entitled Analogous a,a -bis-carbenoid triply bonded species Synthesis of a stable X -phosphinocarbene-X -phosphaacetylene . [21] Again, we were focussed on the multiple bond nature of our compound 17. However, in the last paragraph, we reported that pyrolysis of 17 at 300°C under vacuum, afforded the five-membered heterocycle 22 (as a mixture of four diastereomers), probably via the insertion of the singlet carbene... 

Carbenes are chemical species that possess a bivalent carbon atom with two nonbonding electrons. The divalent carbenes were considered as highly reactive intermediates, and the isolation of stable carbenes has been a challenge for a long time. Based on Wanzlick et al. s work in 1960, Arduengo et al. [1] reported the synthesis of stable imidazolium carbenes in 1991. Independently, Bertrand and coworkers [2] reported the synthesis of phosphinocarbene in 1988. In 1995, Enders et al. [3] reported the synthesis of triazolium carbenes. 

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