Synthesis and Insertion Behavior of Carbonylhydridonitrosyltris(trimethylphosphine)tungsten(0)

Two routes for the synthesis of mer-W(CO)(H)(NO)(PMe3)3 (4) are described, starting from mer-W(Cl)(CO)(NO)(PMe3)3 (1) or the borohydride complex mer-W(η1-BH4)(CO)(NO)(PMe3)3 (3). The propensity of 4 to undergo insertion reactions has been investigated. 4 reacts with benzaldehyde, propionaldehyde, pivalaldehyde, benzophenone, acetophenone, and acetone to afford the corresponding alkoxide complexes mer-W(CO)(NO)(PMe3)3(OCHR‘R‘ ‘) (R‘ = H, R‘ ‘ = Ph (5a); R‘ = H, R‘ ‘ = CH2CH2CH3 (5b); R‘ = H, R‘ ‘ = CH2C(CH3)3 (5c); R‘ = Ph, R‘ ‘ = Ph (5d); R‘ = CH3, R‘ ‘ = Ph (5e); R‘ = CH3, R‘ ‘ = CH3 (5f)). Insertion of CO2 yields the formato-O complex mer-W(CO)(NO)(OCHO)(PMe3)3 (6). Reaction of 4 with CO leads to immediate loss of PMe3 and formation of trans,trans-W(CO)2(H)(NO)(PMe3)2. In a reversible way Fe(CO)5 and Re2(CO)10 insert into the W−H bond of 4, affording the isolable μ-formyl complex mer-W(CO)(NO)(PMe3)3[(μ-OCH)Fe(CO)4] (7a) and mer-W(CO)(NO)(PMe3)3[(μ-OCH)Re2(CO)9] (7b) as an equilibrium constituent. For b...