Unsaturated di:ester prepn. from di:olefin - by oxidising catalytic carbonylation with enol ether and alcohol

摘要

The prepn. of an unsatd diester of formula (where R is ROOC.CHR1C(R3)=C(R4)R2CHCOOR) (1) 1-5C alkyl or aralkyl contg. 6C in the ring and 1-4C in the alkyl, and R1 to R4 are H, halogen, 1-4C alkyl or an aryl gp. contg. 6C in the ring), is claimed. Process comprises reacting a diolefin of formula with R1HC=C(R3)-C(R4)=CHR2 (II) a mixt of CO, O2 and an at least stoichiometric amt. of enol ether or alkoxycycloalkor and an least equal molar amt. of an aliphatic alicyclic or aralkylic satd. monohydric alcohol, at a pressure of 1-05-350 kg/cm2 and at 25-200 degrees C. Reaction is in presence of a catalyst comprising cpd(s). of Pt gp. metal and an oxidising salt of Cu (I), Cu (II), Fe (II) or Fe (III). The diester may be used as a precursor for adipic acid or may be hydrogenater to form dialkyl adipates which are useful as plasticisers and lubricant. the process gives high conversion of the diolefin (II), esp 1,3-butadiene, and excellent selectivity of diester yield.