pH 和波长依赖性的酮洛芬光脱羧作用。

pH- and wavelength-dependent photodecarboxylation of ketoprofen.

机构信息

Department of Chemistry, Beijing Normal University , Xin-wai-da-jie 19#, Beijing 100875, People's Republic of China.

出版信息

Org Lett. 2011 Oct 21;13(20):5472-5. doi: 10.1021/ol202182k. Epub 2011 Sep 21.

DOI:10.1021/ol202182k

PMID:21936485

Abstract

The pH- and wavelength-dependent pathways for the photodecarboxylation of ketoprofen (KP) were mapped by CASSCF/CASPT2 computations. The decarboxylation of the basic form (KP(-)) was found to start from a long-distance charge transfer (CT) excited state when populated by photoexcitation at 330 nm. A short-distance CT excited state populated with photoexcitation at λ < 260 nm appears to be responsible for the decarboxylation of the acidic form (KP). The H(2)O molecules function as a bridge to assist proton transfer in the reactions examined here.

摘要

通过 CASSCF/CASPT2 计算，描绘了酮洛芬（KP）光脱羧的 pH 和波长依赖性途径。研究发现，在 330nm 光激发时，碱性形式（KP(-)）的脱羧反应从长程电荷转移（CT）激发态开始。而在 λ < 260nm 光激发时，生成的短程 CT 激发态则可能负责酸性形式（KP）的脱羧反应。H(2)O 分子在这里的反应中充当桥，协助质子转移。