108059-86-5Relevant articles and documents
Comparison of photoenolization and alcohol release from alkyl-substituted benzoyl benzoic esters
Muthukrishnan, Sivaramakrishnan,Pace, Tamara C.S.,Li, Qian,Seok, Brian,De Jong, Gerdien,Bohne, Cornelia,Gudmundsdottir, Anna D.
, p. 331 - 338 (2011)
Photolysis of 1B in argon-saturated solutions yields 4B and releases methanol. Laser flash photolysis of 1B shows formation of biradical 2B, which has a lifetime of ～50 ns and a max at 330 nm. Biradical 2B undergoes an intersystem crossing to form photoenols E-3B and Z-3B with a max at 390 nm. Laser flash photolysis shows that the lifetimes of E-3B and Z-3B are affected by the solvent. Density functional theory calculations demonstrate that the transition-state barrier for a 1,5-H atom shift from Z-3B to regenerate 1B is affected by the ortho-alkyl substituents, whereas the stereoelectronics of the alkyl substituent affect the transition-state barrier of E-3B as it undergoes electrocyclic ring closure to form 4B. The photoreactivity of 1B was compared with its analogous methyl and isopropyl derivatives 1A and 1C, respectively,to better estimate the effect of the alkyl substituent on reactivity.
