1016227-66-9Relevant academic research and scientific papers
Reaction of metal carbonyl anions with electrophilic alkynes: Synthesis of isomeric η3-acryloyl and σ-vinyl complexes
Adams, Harry,Blenkiron, Peter,Gill, Louise J.,Hervé, Raoul,Huesmann, Anne-G?nke,Morris, Michael J.
, p. 709 - 716 (2008)
Treatment of the metal carbonylate anions [CpMo(CO)2(L)]- (Cp = η-C5H5; L = PPh2Me, PPh2Et) with the electrophilic alkynes methyl propiolate or DMAD (RC{triple bond, long}CCO2Me, where R = H or CO2Me, respectively) followed by protonation affords the η3-acryloyl (1-oxoallyl) complexes [CpMo(η3-COCR{double bond, long}CHCO2Me)(CO)(L)] (3a-d) as the major products, together with the isomeric vinyl complexes trans-[CpMo(CR{double bond, long}CHCO2Me)(CO)2(L)] (4a-d). On the basis of the regioselectivity of the reaction, it is proposed that nucleophilic attack of the carbonylate anion occurs at the alkyne carbon bearing R; migration of the anionic vinyl ligand to a CO followed by protonation gives 3, whereas protonation without insertion gives 4. The X-ray structures of the acryloyl complex [CpMo(η3-COCH{double bond, long}CHCO2Me)(CO)(PPh2Me)] (3b) and its vinyl isomer [CpMo(σ-CH{double bond, long}CHCO2Me)(CO)2(PPh2Me)] (4b) have been determined.
