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Photochemistry of Unsaturated Ketones in Solution. 5 1. Photophysical and Photochemical Studies of Michler’s Ketone’ David I. Schuster,* Marc D. Goldstein, and Penina Bane Contribution from the Department of Chemistry, New York University, New York, New York 10003. Received April 30, 1976
Abstract: Various aspects of the photochemical behavior of Michler’s ketone (MK) in solution have been clarified through steady-state and flash excitation experiments. The triplet yield for MK is strongly solvent dependent, from values near unity in hydrocarbon solvents to very small values in alcoholic media. The primary product in dilute cyclohexane solutions has been isolated and identified as Michler’s pinacol; the same product is formed very inefficiently in dilute 2-propanol and is destroyed on further irradiation at 254 nm. The quantum efficiency for MK disappearance at 366 nm has been determined to be 0.42 in in 2-propanol. Flash absorption studies are complicated by the formation and decay of several radcyclohexane and
