Nucleophilic Attack on Other Atoms

Nucleophilic Attack on Other Atoms.—Amidoximes have been shown to react with tris(dimethylamino)phosphine by displacing dimethylamine to give the phosphine oxides (52), but some N-substituted aromatic amidoximes give derivatives of (53).  

A convenient aziridine synthesis using 2-iodoalkyl azides and triphenyl-phosphine has been reported. The reaction is stereospecific and is thought to proceed by attack of the phosphine on azide  

Mercaptans have been oxidized with diethyl azodicarboxylate and triphenylphosphine. It is suggested that the formation of a charge-transfer complex (57) may be a key step in the reaction. 

An ylide (58) is formed when tetrakis(trifluoromethyl)cyclopenta-dienone and triphenylphosphine are mixed in dichloromethane.  

Bis(trifluoromethyl)nitroxide displaces the dimethylamino-group from tris(dimethylamino)phosphine to form (59). 

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