A Novel Method To Prepare Hydride−Phosphinito Complexes

Abstract

The cyclopentadienyl complex Os(η 5 -C 5 H 5 )Cl(P i Pr 3 ) 2 ( 1 ) reacts with diphenylphosphine to give the mixed-ligand compound Os(η 5 -C 5 H 5 )Cl(PHPh 2 )(P i Pr 3 ) ( 2 ). Treatment of 2 with TlPF 6 in humid acetone and in methanol affords the cationic dihydride complexes [OsH 2 (η 5 -C 5 H 5 ){P(OR)Ph 2 }(P i Pr 3 )]PF 6 (R = H ( 3 ), CH 3 ( 4 )), respectively. Similarly, the treatment of 2 with TlPF 6 in (CD 3 ) 2 CO containing D 2 O and in CD 3 OD gives the deuterated complexes [OsHD(η 5 -C 5 H 5 ){P(OR)Ph 2 }(P i Pr 3 )]PF 6 (R = D ( 3 - d 2 ), CD 3 ( 4 - d 4 )). The reaction of 3 with NaOCH 3 produces its deprotonation and the formation of the dihydride−phosphinito derivative OsH 2 (η 5 -C 5 H 5 ){P(O)Ph 2 }(P i Pr 3 ) ( 5 ). Under the same conditions, the deprotonation of 4 yields OsH(η 5 -C 5 H 5 ){P(OMe)Ph 2 }(P i Pr 3 ) ( 6 ) as a result of the extraction of one of the two hydrides. The treatment of 3 - d 2 with NaOMe selectively affords OsHD(η 5 -C 5 H 5 ){P(O)Ph 2 }(P i Pr 3 ) ( 5 - d ).