Rhodium carbonyl-catalyzed carbonylation of unsaturated compounds V. Cross-hydrocarbonylation of 1-alkyne and ethylene by rhodium carbonyl catalyst modified with phosphines

Article abstract of DOI:10.1016/0022-328X(91)86063-V

In the presence of Rh4(CO)12 catalyst modified with triphenylphosphine the cross-hydrocarbonylation of 1-alkyne (RC2H; R = Me, Et, ⁿPr, ⁿBu, and ^tBu) and ethylene using 2-propanol as the hydrogen donor gives 3-alkyl-5-ethyl-2(5H)-furanone (4, 44-69percent), along with a small amount of 4-alkyl-5-ethyl-2(5H)-furanone (5, 1-8percent). when acetylene itself is used, γ-caprolactone (6a), which is the hydrogenation product of the expected 5-ethyl-2(5H)-furanone (4a), is obtained.The yield of 6a depends on the nature of the phosphine employed and decreases in the following order: PR3 = P(C6H4F-p)3 > PPh3 > P(C6H4Me-p)3 > P(C6H4OMe-p)3 > PPh2Et > PPhEt2 > PEt3.