The versatile coordination behavior of the P(4)butterfly complex [{Cp*Cr(CO)(3)}(2)(mu,eta(1:1)-P-4)] (1) towards Lewis acidic pentacarbonyl compounds of Cr, Mo and W is reported. The reaction of1with [W(CO)(4)(nbd)] (nbd=norbornadiene) yields the complex [{Cp*Cr(CO)(3)}(2)(mu(3),eta(1:1:1:1)-P-4){W(CO)(4)}] (2) in which1serves as a chelating P(4)butterfly ligand. In contrast, reactions of1with [M(CO)(4)(nbd)] (M=Cr (a), Mo (b)) result in the step-wise formation of [{Cp*Cr(CO)(2)}(2)(mu(3),eta(3:1:1)-P-4){M(CO)(5)}] (3 a,b) and [{Cp*Cr(CO)(2)}(2)-(mu(4),eta(3:1:1:1)-P-4){M(CO)(5)}(2)] (4 a,b) which contain a folded cyclo-P(4)unit. Complex4 aundergoes an unprecedented P-1/P-3-fragmentation yielding the cyclo-P(3)complex [Cp*Cr(CO)(2)(eta(3)-P-3)] (5) and the as yet unknown phosphinidene complex [Cp*Cr(CO)(2){Cr(CO)(5)}(2)(mu(3)-P)] (6). The identity of6is confirmed by spectroscopic methods and by the in situ formation of [{Cp*Cr(CO)(2)(tBuNC)}P{Cr(CO)(5)}(2)(tBuNC)] (7). DFT calculations throw light on the bonding situation of the reported products.