Preparation and Characterization of a Monocyclopentadienyl Osmium−Allenylcarbene Complex
摘要:
The dihydride-dihydrogen complex [OsH2(eta(5)-C5H5)(eta(2)-H-2)((PPr3)-Pr-i)]BF4 (1) reacts with phenylacetylene to give the allenylcarbene derivative [Os(eta(5)-C5H5){=CPh(eta(2)-CH = C = CHPh)}((PPr3)-Pr-i)]BF4 (2) via the,pi-phenyl acetylene intermediate [Os(eta(5)-C5H5)(eta(2)-PhC CH)((PPr3)-Pr-i)]BF4 (3). The reactions of 2 with NaOMe and LiC CPh afford 3:1 mixtures of two hydride-osmaindene isomers of formula OsH(eta(5)-C5H5){C(C CPh)=CHC6H4}((PPr3)-Pr-i) (4 and 5) instead of the expected osmabenzyne complex.