Dicoordinated phosphorus compounds: a novel 4,5-disubstituted 1,2,4,3-triazaphosphole. X-Ray molecular strucutures of a 2-N-BF3 complex of 4,5-diisopropyl-1,2,4,3-triazaphosphole and of its tetramer. Conformation in the crystalline form and in solution

The synthesis of the title compound is described. It may be stabilised by the reaction of its tetramer with BF3. The tetramer displays several isomers and conformers in solution; one of them has been isolated and its crystal structure determined. The crystal structure of the 2-N-BF3 complex of the parent 4,5-diisopropyl-1,2,4,3-triazaphosphole has also been obtained.