Effect of alkyl substituents on photorelease from butyrophenone derivatives

S Muthukrishnan, J Sankaranarayanan…

Index: Muthukrishnan, Sivaramakrishnan; Sankaranarayanan, Jagadis; Klima, Rodney F.; Pace, Tamara C. S.; Bohne, Cornelia; Gudmundsdottir, Anna D. Organic Letters, 2009 , vol. 11, # 11 p. 2345 - 2348

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Citation Number: 15

Abstract

Photolysis of 1a yields 4a in argon-saturated methanol, whereas 1b is photostable. Laser flash photolysis of 1a in acetonitrile shows formation of biradical 2a (λmax= 340 nm, τ=∼ 60 ns), which undergoes intersystem crossing to form Z-3a (λmax= 380 nm, τ= 270 ns) and E- 3a (λmax= 380 nm, τ= 300 ms). Z-3a regenerates the starting material, whereas E-3b undergoes intramolecular lactonization to release the alcohol moiety and form 4a. Similar ...