Hydrocyanation processes and multidentate phosphite ligand and nickel catalyst compositions therefor

A hydrocyanation process comprising reacting an acyclic, aliphatic, monoethylenically unsaturated compound in which the ethylenic double bond is not conjugated to any other olefinic group in the molecule, or a monoethylenically unsaturated compound in which the ethylenic double bond is conjugated to an organic ester group, with a source of HCN in the presence of a catalyst precursor composition comprising a Lewis acid, a zero-valent nickel, and at least one multidentate phosphite ligand selected from the group represented by the following Formulas I, II, III, IV, V, VI, VII, VIII, and IX:

• ##STR32## wherein each R.sup.1 is independently a primary, secondary, or tertiary hydrocarbyl of 1 to 12 carbon atoms;
• with the proviso that at least one of R.sup.1 must be a primary hydrocarbyl;
• each R.sup.2 is independently H, halogen, primary or secondary hydrocarbyl of 1 to 12 carbon atoms, OR.sup.3 wherein R.sup.3 is a C.sub.1 to C.sub.12 alkyl, or CO.sub.2 R.sup.3 ' wherein R.sup.3 ' is an aryl or a C.sub.1 to C.sub.12 alkyl;
• each R.sup.2 ' is independently H, halogen, CHO, primary, secondary or tertiary hydrocarbyl of 1 to 12 carbon atoms, OR.sup.3 wherein R.sup.3 is a C.sub.1 to C.sub.12 alkyl, CO.sub.2 R.sup.3 ' wherein R.sup.3 ' is an aryl or a C.sub.1 to C.sub.12 alkyl, or C(R.sup.3)(O) wherein R.sup.3 is a C.sub.1 to C.sub.12 alkyl;
• each R.sup.4 is independently H, a primary or secondary hydrocarbyl of 1 to 12 carbon atoms or CO.sub.2 R.sup.3 wherein R.sup.3 is a C.sub.1 to C.sub.12 alkyl;
• and
• each R.sup.4 ' is independently H, a primary or secondary hydrocarbyl of 1 to 12 carbon atoms or aryl.