Patent ID: 8252874

Claim:
A ligand having the general formula (I): (R 1 ) 2 P—P(R 1 ) m (R 2 ) n ═N(R 3 ) (I) wherein R 3 is selected from hydrogen, a hydrocarbyl group, a substituted hydrocarbyl group, a heterohydrocarbyl group, a substituted heterohydrocarbyl group, or a silyl group; the R 1 groups are independently selected from an optionally substituted aromatic group bearing a polar substituent on at least one of the ortho-positions; and the R 2 groups are independently selected from hydrocarbyl, substituted hydrocarbyl, heterohydrocarbyl and substituted heterohydrocarbyl groups with the proviso that when the group is aromatic it does not contain a polar substituent at any of the ortho-positions; with the proviso that m is 0 or 1, n is 1 or 2 and the total of m+n is 2.