Synthesis of [M(CO)4(Ph2PCHRPPh2)](M = Cr, Mo, or W; R = COPh or COC6H4Me-p) and photochemically induced reactions of the complex [W(CO)4{Ph2PCH(COPh)PPh2}]: crystal structures of the complexes [W(CO)4{Ph2POC(Ph)CHPPh2}] and [W(CO)4(PPh2OH)(PPh2CH2COPh)]

Abstract

Compounds of type [[graphic omitted]Ph₂)](M = Cr, Mo, or W) are deprotonated by LiBuⁿ and the resultant carbanions are acylated by RCOCl (R = Ph or C₆H₄Me-p) to give the complexes [[graphic omitted]Ph₂}]. These acylated complexes react with NaOMe, reversibly, to give enolate anions [[graphic omitted]Ph₂}] or with RCOCl/pyridine to give the complex [[graphic omitted])₂CCR(OCOR)}]. Irradiation of [[graphic omitted]Ph₂}] gives, initially, the six-membered-ring chelate complex [[graphic omitted]Ph₂}](3a), which is in turn converted into [W(CO)₄(PPh₂OH)(PPh₂CH₂COPh)](4a) in the presence of light and traces of water. Crystals of both (3a) and (4a) are monoclinic, space group P2₁/c, with Z= 4. Those of (3a) have a= 17.013(3), b= 10.454(2), c= 19.723(3)Å, and β= 114.23(1)°. Those of (4a) have a= 18.629(3), b= 9.931 (1), c= 18.182(4)Å, and β= 94.58(1)°. Final R factors were 0.030 for 3 634 and 0.068 for 4 027 observed reflections, respectively.