311347-70-3Relevant academic research and scientific papers
Reactions of [Mo2(u-RC2R)(CO)4Cp2] (R = CO2Me, Cp = η-C5H5) with P2Ph4, PPh2H and R1SH (R1 = Et, Pr', C6H4Me-/; or Bul): Stabilisation of u-vinyl complexes by chelating substituents
Adams, Harry,Biebricher, Andreas,Gay, Sally R.,Hamilton, Trcvor,McHugh, Paul E.,Morris, Michael J.,Mays, Martin J.
, p. 2983 - 2989 (2007/10/03)
The dimolybdenum alkyne complex [Mo2(u-C2R2)(CO)4Cp2] 1 (R = CO2Me; Cp = n-C5H5) reacts with P2Ph4 to afford three major products, which have been identified as the phosphido-bridged vinyl complexes cis- and tram[Mo2(u-CR=CHR)(u-PPh2)(CO)2Cp2] (two separable isomers, 2 and 3 respectively) and [Mo2(u-CR=CRCHO)(u-PPh2)(CO)2Cp2] 4. The crystal structure of 3 has been determined and shows that the CO2Me group attached to the β-carbon of the vinyl ligand is co-ordinated to one metal atom through the carbonyl group, thus forming a five-membered chelate ring. The reaction of 1 with PPh2H in refluxing toluene gave the same three complexes, whereas treatment of 1 with PPh2H at room temperature in the presence of trimethylamine W-oxide afforded the monosubstituted complex [Mo2(u-C2R2)(CO)3(PPh 2H)Cp2] 6 together with a small amount of 4; thermolysis of 6 also yields 2, 3 and 4. Treatment of 1 with thiols R'SH (R1 = Et, Pr1 or C6H4Me-/>) afforded the complexes [Mo2(u-CR=CHR)(n-SR')(CO)2Cp2] 7a-7c which are analogous to 3; the structure of the complex with R1 = Pr1 has been determined. In contrast, treatment of 1 with Bu'SH affords the unusual complex [Mo2(u-S)2(u-RCH=CHR)Cp2] 8 in which the alkyne ligand has been hydrogenated to an alkene which is bonded in an r|2 manner to one metal atom and through both CO2Me groups to the other. The complexes [Mo2(u-CH=CHR)(u-SR')(CO)2Cp2] 10, derived from the methyl propiolate complex [Mo2(u-HC2R)(CO)4Cp2], are also described. The Royal Society of Chemistry 2000.
