presence of triethylamine with 254 nm light initiates photoreduction and photoepimerization of the 6-keto and 17-keto functionalities, respectively. A two-step intramolecular singlet-singlet energy transfer mechanism is proposed to explain the photoepimerization.
                                    在
三乙胺存在下,在254 nm光线下,
乙腈中3α-二甲基苯基甲
硅烷氧基
5α-雄烷-6,17-二酮的光解分别引发6-酮和17-酮官能团的光还原和光致电子异构化。提出了两步的分子内单线态-单态能量转移机理来解释光致电子化。