Cu(II)-Catalyzed 6π-Photocyclization of Non-6π Substrates
摘要:
This research successfully achieved a Cu(II)-catalyzed 6 pi-photocyclization of non-6 pi substrates. The photo-enolization converts ortho-alkylphenyl alkynl ketones into a triene-type intermediate which undergoes the subsequent 6 pi-photo- facilitates both photoenolization and 6 pi-photocyclization. This research highlighted the tandem reaction strategy and the importance of metal catalysis in photochemistry.
作者:Brian J. Groendyke、Deyaa I. AbuSalim、Silas P. Cook
DOI:10.1021/jacs.6b08171
日期:2016.10.5
This communication describes a mild, amide-directed fluorination of benzylic, allylic, and unactivated C-H bonds mediated by iron. Upon exposure to a catalytic amount of iron(II) triflate (Fe(OTf)2), N-fluoro-2-methylbenzamides undergo chemoselective fluorine transfer to provide the corresponding fluorides in high yield. The reaction demonstrates broad substrate scope and functional group tolerance
该通讯描述了由铁介导的苄基、烯丙基和未活化的 CH 键的温和、酰胺导向氟化。在接触催化量的三氟甲磺酸铁 (II) (Fe(OTf)2) 后,N-氟-2-甲基苯甲酰胺进行化学选择性氟转移,以高产率提供相应的氟化物。该反应显示出广泛的底物范围和官能团耐受性,无需使用任何贵金属添加剂。机理和计算实验表明,反应通过短寿命的自由基中间体进行,F-转移直接由铁介导。
Acid–base-sensitive allylic oxidation of 2-allylbenzoic acids to form phthalides
作者:Le Thi Ngoc Chuc、Thi Anh Hong Nguyen、Duen-Ren Hou
DOI:10.1039/d0ob00303d
日期:——
corresponding phthalides selectively. Mechanistic studies, including the corresponding reaction of (E)-2-(1-propenyl)benzoicacid to 3-methylisocoumarin, isomerization reaction of 3-vinylphthalide to 3-ethylidenephthalide, and the kinetic isotope effect using 2-(1,1-d2-allyl)benzoicacid, revealed the competition between Wacker-type oxidation and allylic C-H cleavage, which is the key step to generating
iron/photoredox dual-catalyzed acyl nitrene formation and the use of acyl nitrene in constructing various C–O bonds towards phthalides. The developed reaction starts from N-methoxyl-2-alkylbenzamides. Mechanism surveys suggest the reaction involves iron nitrene-based hydrogen atom abstraction (HAA), radical-polar crossover and O-nucleophilic SN1. Distinctively, the often-reported radical rebound in previous publications
本文描述了铁/光氧化还原双催化酰基氮烯的形成以及酰基氮烯在构建各种 C-O 键中对苯酞的应用。开发的反应从N -methoxyl-2-alkylbenzamides 开始。机理调查表明,该反应涉及基于铁氮烯的氢原子提取 (HAA)、自由基-极性交叉和O-亲核 S N 1。值得注意的是,未观察到以前出版物中经常报道的自由基反弹。该反应代表了基于酰基氮烯的苯酞合成的第一个例子。此外,它还作为合成3-丁基苯酞(NBP)、沙利度胺、Pomalyst和Otezia等市售药物的补充剂。
SHIH, CHUAN;SWENTON, J. S., J. ORG. CHEM., 1982, 47, N 13, 2668-2670