Journal
ORGANOMETALLICS
Volume 23, Issue 4, Pages 647-656Publisher
AMER CHEMICAL SOC
DOI: 10.1021/om0342309
Keywords
-
Categories
Ask authors/readers for more resources
The formation of MeP(O)(OPh)(2) by reductive elimination from L2PdMe(P(O)(OPh)(2)) species has been investigated. The electronic and steric effects of the supporting ligands were investigated by studying reductive elimination reactions from a series of discrete complexes containing nitrogen- and phosphorus-based ligands. The P(O)-C(sp(3)) bond-forming reaction is slow when the intermediate species contains bidentate nitrogen ligands or small basic monodentate phosphines. Analogous complexes bearing large bite angle diphosphines such as dppf and Xantphos undergo reductive elimination at ambient temperature. The rate of MeP(O)(OPh)(2) formation by reductive elimination from (dppf)PdMe(P(O)(OPh)(2)) is not affected by the identity or concentration of added ligand (excess dppf or PPh3) suggesting that the reductive elimination occurs from a four- or three-coordinate intermediate. When the rate of reductive elimination is slow, protonolysis reactions between L2PdMe(P(O)(OPh)(2)) intermediates and HP(O)(OPh)(2) leads to the formation of bis-phosphonate complexes. The protonolysis reaction can be circumvented by the use of large bite angle phosphines such as dppf and Xantphos, which lead to rapid rates of P(O)-C(sp(3)) bond formation. These results demonstrate that the formation of P(O)-C(sp(3)) bonds by reductive elimination from L2PdRP-(O)(OR)(2) complexes is quite sensitive to the steric bulk of the supporting ligand and the presence of excess hydrogen phosphonate.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available