Didier Bourissou, Yves Canac, Maria Isabel Collado, Antoine Baceiredo and Guy Bertrand
Diphosphirenium salt 1 reacts with LiAlH4 leading to P-hydrophosphaalkene 2, which on treatment with a catalytic amount of BF3·OEt2 affords 1H-diphosphirene 3, while with a stoichiometric amount of W(CO)5(thf), complex 4 is obtained.