Light-Mediated Synthesis of 2-(4-Methoxyphenyl)-1-pyrroline via Intramolecular Reductive Cyclization of a Triplet Alkylnitrene
Light-Mediated Synthesis of 2-(4-Methoxyphenyl)-1-pyrroline via Intramolecular Reductive Cyclization of a Triplet Alkylnitrene
复制标题
通过三重态烷基氮烯的分子内还原环化光介导合成 2-(4-甲氧基苯基)-1-吡咯啉
DOI：
10.1021/acs.orglett.3c01476
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发表时间：
2023
期刊：
影响因子：
5.2
通讯作者：
Abe, Manabu
中科院分区：
文献类型：
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作者：
George, Sobiya;Govorov, Dmitrii;Gatlin, DeVonna M.;Merugu, Rajkumar;Wasson, Fiona J.;Shields, Dylan J.;Allen, Yasmine;Muthukrishnan, Sivaramakrishnan;Krause, Jeanette A.;Abe, Manabu
对甲氧基叠氮丁苯酮(1)在甲醇中辐射生成2-(4-甲氧基苯基)-1-吡咯啉(2)和其他几种光产物。然而，在三(三甲基硅基)硅烷(TTMSS)存在下，选择性地生成2。瞬时吸收光谱和电子自旋共振光谱证实，1通过分子内能量转移从三线态酮(T1K)中形成了三线态烷基氮31N。密度泛函理论计算表明，31N从TTMSS中提取H原子，但不从甲醇中提取H原子，这解释了选择性。因此，三重烷基氮烯可以通过从TTMSS中提取氢原子进行选择性还原环化反应。
Irradiation ofp-methoxyazidobutyrophenone (1) in methanol yielded 2-(4-methoxyphenyl)-1-pyrroline (2) and several other photoproducts. However, in the presence of tris(trimethylsilyl)silane (TTMSS),2is formed selectively. Transient absorption and ESR spectroscopy verify that the irradiation of1forms triplet alkylnitrene31Nthrough intramolecular energy transfer from the triplet ketone (T1K). DFT calculations indicate that31Nabstracts H atoms from TTMSS but not methanol, which explains the selectivity. Thus, triplet alkylnitrenes can undergo selective reductive cyclization via H atom abstraction from TTMSS.