α-硫代苯基-α'-硫代苯基-S,S-二氧代取代酮的意外固态光化学

Unexpected solid-state photochemistry of an alpha-thiophenyl-alpha'-thiophenyl-S,S-dioxo-substituted ketone.

作者信息

Resendiz Marino J E, Taing Jennifer, Khan Saeed I, Garcia-Garibay Miguel A

机构信息

Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095-1569, USA.

出版信息

J Org Chem. 2008 Jan 18;73(2):638-43. doi: 10.1021/jo702127g. Epub 2007 Dec 23.

DOI:10.1021/jo702127g

PMID:18154353

Abstract

Samples of 2,4-dimethyl-2-(thiophen-3-yl)-4-(thiophen-3-yl-S,S-dioxo)pentan-3-one 2 were obtained by controlled MCPBA oxidation of 2,4-dimethyl-2,4-di(thiophen-3-yl)pentan-3-one 1. Rather than the expected photodecarbonylation, UV--vis irradiation of 2 led to the intramolecular 2 + 2 photocycloaddition product 5 in quantitative yields (by GC and NMR) both in solution and in crystalline solid state. Detailed X-ray powder diffraction analyses revealed that the solid-state reaction of sulfone 2 occurs with a loss of long-range order despite retaining some birefringence under polarized microscopy.

摘要

通过对2,4-二甲基-2,4-二(噻吩-3-基)戊-3-酮1进行可控的间氯过氧苯甲酸(MCPBA)氧化反应，得到了2,4-二甲基-2-(噻吩-3-基)-4-(噻吩-3-基-S,S-二氧代)戊-3-酮2的样品。2经紫外-可见光照后，并未发生预期的光脱羰反应，而是在溶液和结晶固态中均以定量产率(通过气相色谱和核磁共振)生成了分子内2 + 2光环加成产物5。详细的X射线粉末衍射分析表明，砜2的固态反应发生时失去了长程有序性，尽管在偏光显微镜下仍保留了一些双折射现象。