Beiträge zur Chemie des Phosphors. 94. Tetraphenyl-cyclotetraphosphan, (PPh)4, und 1,2,3-Triphenyl-4-tert-butyl-cyclotetraphosphan, (PPh)3(PBut)

Contributions to the Chemistry of Phosphorus. 94. Tetraphenyl-cyclotetraphosphane, (PPh)₄, and 1,2,3-Triphenyl-4-tert-butyl-cyclotetraphosphane, (PPh)₃(PBu^t) The homocyclic four-membered phosphorus ring compounds tetraphenyl-cyclotetra-phosphane, (PPh)₄ ( 1 ), and l,2,3-triphenyl-4-tert-butyl-cyclotetraphosphane, (PPh)₃(PBu^t) ( 2 ), are obtained as main products by 3+l]-cyclocondensation of K(Ph)P? P(Ph)? P(Ph)K or Me₃Si(Ph)P? P(Ph)? P(Ph)SiMe₃ with PhPCl₂ or Bu^tPCl₂ respectively under suitable reaction conditions. At room temperature in solution 1 rearranges mostly to the oligomeric (PPh)₅, whereas 2 is remarkably stable. The ³¹P-NMR parameters of the mixed substituted four-membered ring compound 2 are reported and discussed.