1. "Rhodium-Mediated Stoichiometric P=C Bond Cleavage and Catalytic Isomerization in Phosphacumulenes," Marie-Anne David, Sara N. Paisner, and David S. Glueck, Organometallics 1995, 14, 17-19.

The phosphacumulenes Mes*P=C=O and Mes*P=C=NPh [1-2; Mes* = 2,4,6-(t-Bu)₃C₆H₂] undergo P=C bond cleavage on reaction with Rh(PCy₃)₂Cl (4a, Cy = cyclo-C₆H₁₁) to form the phosphaindan [2,4-(t-Bu)₂C₆H₂(6-CMe₂CH₂PH)] (5) and trans-Rh(PCy₃)₂Cl(CO) (6) and trans-Rh(PCy₃)₂Cl(CNPh) (7) respectively. In contrast, Mes*P=C=CPh ₂ (3) is catalytically rearranged to its isomer, phospha-indan derivative [2,4-(t-Bu)₂C₆H₂(6-CMe₂CH₂PCH=CPh₂)] (8) using 4a and the related complexes [Rh(PPh₃)₃Cl] (4b) and [Rh(PPh₃)₂Cl]₂ (4c) as catalyst precursors. An intermediate in isomerization catalyzed by 4a, [Rh(PCy₃)(Mes*P=C=CPh₂)Cl]_n (9a), which is itself an active catalyst for the isomerization, was isolated. Spectroscopic evidence suggests that it contains an h²&endash;(P,C)&endash;bound phospha-allene ligand.