Metallinduzierte und basenkatalysierte 2‐Propinyl‐Allenyl‐Umlagerung in [(HCCCH2)(2,4,6‐tBu3C6H2O)]PMoCP(CO)2

Abstract

Metal‐Induced and Base‐Catalyzed 2‐Propynyl‐Allenyl Rearrangement in [(HCCCH2)(2,4,6‐tBu3C6H2O)]PMoCP(CO)2The synthesis and reactivity of [(HCCCH2)(2,4,6‐tBu31‐C6H2O)]PMoCp(CO)2 (3) is described. [(HCCCH2)(R)]PCl (1) reacts with NaMoCp(CO)3 (2) to afford the s̀3,λ41‐phosphanediyl compounds 3. With NEt3 a prototropic rearrangement of the 2‐propynyl ligand of 3 to an allenyl group in [(H2CCCH)(R)]PMoCp(CO)2 (5) is observed. However, with Cr(CO)5 · THF a metal‐induced rearrangement of the 2‐propynyl unit in 3 yields η3‐{(2,4,6‐tBu3C6H2O)[(CO)5Cr]PCHCCH2}MoCp(CO)2 (7). Complex 7 contains a 1‐phosphaallyl system, which is functionalized by an exocyclic CC double bond X‐ray structure analyses of 3 and 7 are performed.