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Updated: Oct 3, 2026

Preparation and Use of Carbonyl-decorated Carbenes in the Activation of White Phosphorus
Published on: October 3, 2014
Carbene-Pnictinidene Adducts
Anthony J. Arduengo1, Joseph C. Calabrese, Alan H. Cowley
1DuPont Science and Engineering Laboratory,(5) Experimental Station, Wilmington, Delaware 19880-0328, and Department of Chemistry and Biochemistry, The University of Texas at Austin, Austin, Texas 78712-1167.
Abstract:
The syntheses, characterizations, and X-ray crystallographic structure determinations are described for adducts of stable nucleophilic carbenes with pnictinidenes. The adducts between 1,3-dimesitylimidazol-2-ylidene and phenylphosphinidene, phenylarsinidene, (trifluoromethyl)phosphinidene, and (pentafluorophenyl)arsinidene are reported. These carbene-pnictinidene adducts are formed by the direct reaction of a stable nucleophilic carbene with the corresponding pnictinidene cyclic oligomers. The synthesis and structure of the adduct between 1,3-dimesitylimidazolin-2-ylidene and phenylphosphinidene from the reaction of 1,3-dimesitylimidazolin-2-ylidene with phenylphosphorus dichloride are also reported. These carbene-pnictinidene adducts possess strongly polarized pnictinidene-carbene bonds. The C-Pn-C angles are all typically small at 97-102 degrees, and there is only a 4% shortening of the nominal Pn=C double bond compared to the Pn-C single bond to the second substituent on the pnictogen. The (31)P NMR shifts of the phosphorus adducts suggest strongly shielded phosphorus centers in accord with the polarized structures.
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