A. Lledos et al., Strong 1,4-P-O intramolecular interactions as a source of conformational preferences in alpha-stabilized phosphorus ylides, INORG CHEM, 40(19), 2001, pp. 4913-4917
For the first time, the existence of a strong intramolecular 1,4-interactio
n between the phosphorus atom and the oxygen atom in alpha -keto-stabilized
ylides has been demonstrated by means of theoretical calculations. This in
teraction has a notable influence on the conformational preferences and rot
ational barriers of alpha -stabilized phosphorus ylides and bis-ylides.