R. Lopez et al., SOLVENT EFFECTS ON THE STEREOSELECTIVITY OF KETENE-IMINE CYCLOADDITION REACTIONS, Journal of the Chemical Society, Chemical Communications, (16), 1995, pp. 1677-1678
According to ab initio computations, the electrostatic solute-solvent
interactions are predicted to be critical in the control of the stereo
selectivity of the [2 + 2] ketene-imine cycloaddition reactions caused
by the torquoelectronic effect.