Process for the preparation of alkyl nonadienoate esters

A process for reacting a mixture of 1,3-butadiene, carbon monoxide and a monoalkanol of the general formula ROH in which R is a straight or branched chain alkyl group of from 1 to about 12 carbon atoms to provide alkyl non-adienoate employing as a catalyst, a palladium-ligand complex comprising:

• (a) a member selected from the group consisting of zero valent palladium, a palladium-containing composition which can provide zerovalent palladium under reaction conditions and palladium (II) salt;
• (b) a strong ligand selected from the group consisting of tertiary phosphine having a pKa in water of not greater than about 6, a phosphite of the general formula (R.sup.1 O)(R.sup.2 O)(R.sup.3 O)P in which each of R.sup.1, R.sup.2 and R.sup.3 is an alkyl group having at least 9 carbon atoms, an aryl group or an alkaryl group, an arsine of the general formula R.sup.1 R.sup.2 R.sup.3 As in which each of R.sup.1, R.sup.2 and R.sup.3 have the aforestated meanings and a stibine of the general formula R.sup.1 R.sup.2 R.sup.3 Sb in which each of R.sup.1, R.sup.2 and R.sup.3 have the aforestated meanings, the mole ratio of said strong ligand to palladium being from about 1:1 to about 3:1;
• and,
• (c) a weak ligand selected from the group consisting of tertiary phosphine having a pKa in water of greater than about 6, a phosphite of the general formula (R.sup.4 O)(R.sup.5 O)(R.sup.6 O)P in which each of R.sup.4, R.sup.5 and R.sup.6 is an alkyl group having less than 9 carbon atoms, an arsine of the general formula R.sup.7 R.sup.8 R.sup.9 As in which each of R.sup.7, R.sup.8 and R.sup.9 is an alkyl group having less than 9 carbon atoms or an alkoxy group and a stibine of the general formula R.sup.7 R.sup.8 R.sup.9 Sb in which each of R.sup.7, R.sup.8 and R.sup.9 have the aforestated meanings, the mole ratio of said weak ligand to palladium being from about 4:1 to about 100:1, said reaction being carried out in the presence of a catalyst stabilizing amount of alkoxide ion.

A process for reacting a mixture of 1,3-butadiene, carbon monoxide and a monalkanol of the general formula ROH in which R is a straight or branched chain alkyl group of from 1 to about 12 carbon atoms to provide alkyl nonadienoate employing as catalyst, a palladium-ligand complex comprising:

• (a) a member selected from the group consisting of zerovalent palladium, a palladium-containing composition which can provide zerovalent palladium under reaction conditions and palladium (II) salt:
• (b) a strong ligand selected from the group consisting of:
• P(CH.sub.2 CH.sub.2 CN).sub.3, PPh(CH.sub.2 CH.sub.2 CN).sub.2, PPh.sub.3, P(Odecyl)(OPh).sub.2, ##STR6## Ph.sub.2 As--CH.sub.2 CH.sub.2 --AsPh.sub.2, P(CH.sub.2 Ph).sub.3 and AsPh.sub.3, the mole ratio of said strong ligand to palladium being from about 1:1 to about 3:1, and:
• (c) a weak ligand, said weak ligand being PBu.sub.3, the mole ratio of said weak ligand to palladium being from about 4:1 to about 100:1.