title: Solid-state photochromism and photoreactivity of o- and p-anisaldehydes. Remarkable stabilization of o-xylylenols.
abstract: [reaction: see text] All of the crystalline o-anisaldehyde derivatives 1 and 3 change to brick-red color upon brief exposure to UV-vis radiation. The red color, attributed to (E)-xylylenol, is remarkably persistent for hours (ca. 10 h) in the case of 1c; such a long lifetime for the reactive o-xylylenols is unprecedented. In contrast, the p-anisaldehydes 2 undergo cyclization. Solid-state photolysis of 2b affords the benzocyclobutenol 7b regioselectively, which is not accessible from solution-phase photolysis.
authors.affiliation: Department of Chemistry, Indian Institute of Technology, Kanpur 208 016, India.
authors.forename: J N
authors.initials: JN
authors.lastname: Moorthy
authors.forename: P
authors.initials: P
authors.lastname: Mal
authors.forename: R
authors.initials: R
authors.lastname: Natarajan
authors.forename: P
authors.initials: P
authors.lastname: Venugopalan