Photochemical rearrangement of α-chloro-propiophenones to α-arylpropanoic acids: studies on chirality transfer and synthesis of (S)-(+)-ibuprofen and (S)-(+)-ketoprofen
作者:Harikisan R. Sonawane、Nanjundiah S. Bellur、Dilip G. Kulkarni、Nagaraj R. Ayyangar
DOI:10.1016/s0040-4020(01)80835-8
日期:1994.1
α-arylpropanoic acids (4) from α chloro-propiophenones (5) is described. It involves carbonyl triplet excited state directed 1,2-aryl migration of the aryl group which has been found to be highly dependent upon the nature of the aryl substituent. The mode of this rearrangement is probed by the study of the photobehaviour of a set of optically active α-chloro-propiophenones. The results suggest that the nature of
描述了一种新的单步高效光化学方法,可从α氯丙酮(5)中分离出α-芳基丙酸(4)。它涉及芳基的羰基三重激发态定向的1,2-芳基迁移,已发现其高度依赖于芳基取代基的性质。通过对一组光学活性的α-氯-苯乙酮的光行为的研究来探究这种重排的方式。结果表明,羰基三联体(n,π * /π,π *)的性质在手性转移中起重要作用。该方法在光学活性布洛芬(4e)和酮洛芬(26),尽管光学产量中等。