Remarkable Suppression of [2+2] Cycloaddition during Nonresonant Two-photon Photoreaction of trans-Stilbene in the Presence of Tetramethylethylene

Article abstract of DOI:10.1111/j.1751-1097.1997.tb03190.x

Nonresonant two-photon excitation of trans-stilbene in the presence of an excess amount of tetramethylethylene induced predominantly cis-trans isomerization; the [2+2] intermolecular cycloaddition pathway was remarkably suppressed, in contrast to the one-photon excitation under similar conditions, where the cycloaddition is known to be the major pathway.