The reaction of dithiadiphosphetane disulfides with dienes, alkenes and thioaldehydes

Ferrocenyl dithiadiphosphetane disulfide behaves as RPS2 in simple cycloaddition reactions. Reactions with norbornadiene, norbornene and hexamethyl dewar benzene ail give rise to fused 4-membered C2PS ring compounds. Reaction with 2,3-dimethylbutadiene gave a simple Diels-Alder adduct which undergoes further reaction with BuLi and RX to yield FcP(S)(SR)(C6H9) (R = CH2Ph, o-MeC6H4CH2, 2,4-dinitrophenyl). A trithiaphosphorinane was obtained when Fc(2)P(2)S(4) was reacted with benzaldehyde or trimethylacetaldehyde. Reaction of Fc(2)P(2)S(4) with PhCH2N = CHPh gave a dithiophospholane and a thiazadiphosphetane disulfide. The new compounds have been characterised spectroscopically with illustrative examples having been studied by X-ray crystallography.