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[3+2] Fragmentation of a Pentaphosphido Ligand by Cyanide.

ABSTRACT: The activation of white phosphorus (P₄ ) by transition-metal complexes has been studied for several decades, but the functionalization and release of the resulting (organo)phosphorus ligands has rarely been achieved. Herein we describe the formation of rare diphosphan-1-ide anions from a P₅ ligand by treatment with cyanide. Cobalt diorganopentaphosphido complexes have been synthesized by a stepwise reaction sequence involving a low-valent diimine cobalt complex, white phosphorus, and diorganochlorophosphanes. The reactions of the complexes with tetraalkylammonium or potassium cyanide afford a cyclotriphosphido cobaltate anion 5 and 1-cyanodiphosphan-1-ide anions [R₂ PPCN]^- (6-R). The molecular structure of a related product 7 suggests a novel reaction mechanism, where coordination of the cyanide anion to the cobalt center induces a ligand rearrangement. This is followed by nucleophilic attack of a second cyanide anion at a phosphorus atom and release of the P₂ fragment.

SUBMITTER: Hoidn CM

PROVIDER: S-EPMC6972699 | biostudies-literature | 2019 Dec

REPOSITORIES: biostudies-literature

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[3+2] Fragmentation of a Pentaphosphido Ligand by Cyanide.

Hoidn Christian M CM Maier Thomas M TM Trabitsch Karolina K Weigand Jan J JJ Wolf Robert R

Angewandte Chemie (International ed. in English) 20191107 52

The activation of white phosphorus (P4 ) by transition-metal complexes has been studied for several decades, but the functionalization and release of the resulting (organo)phosphorus ligands has rarely been achieved. Herein we describe the formation of rare diphosphan-1-ide anions from a P5 ligand by treatment with cyanide. Cobalt diorganopentaphosphido complexes have been synthesized by a stepwise reaction sequence involving a low-valent diimine cobalt complex, white phosp ...[more]

PMID: 31573718

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