Enantioselective Friedel-Crafts Alkylation of Indoles with (<i>E</i>)-1-Aryl-4-benzyloxybut-2-en-1-ones Catalyzed by an (<i>R</i>)-3,3′-Br<sub>2</sub>BINOLate-Hafnium(IV) Complex
作者:Gonzalo Blay、Isabel Fernández、M. Carmen Muñoz、José R. Pedro、Carlos Vila
DOI:10.1002/ejoc.201201636
日期:2013.4
A highly enantioselectiveFriedel–Crafts reaction of unprotected indoles with (E)-1-aryl-4-benzyloxybut-2-en-1-onescatalyzed by a new chiral [Hf(R)-3,3′-Br2-BINOL}(OtBu)2]2 complex has been developed to functionalize the C-3 position of the indole nucleus with a side chain bearing a 1,4-difunctionalized moiety and a benzylic stereogenic center. The reaction proceeds in good to excellent yields and
Crossed Intermolecular [2+2] Cycloadditions of Acyclic Enones via Visible Light Photocatalysis
作者:Juana Du、Tehshik P. Yoon
DOI:10.1021/ja903732v
日期:2009.10.21
Efficient [2+2] heterodimerizations of dissimilar acyclic enones can be accomplished upon visiblelight irradiation in the presence of a ruthenium(II) photocatalyst. Similar cycloadditions under standard UV photolysis conditions are inefficient and unselective. Nevertheless, a diverse range of unsymmetrical tri- and tetrasubstituted cyclobutane structures can be produced in good yields and excellent
在钌 (II) 光催化剂存在下,在可见光照射下可以实现不同无环烯酮的有效 [2+2] 异二聚化。在标准 UV 光解条件下,类似的环加成是低效且无选择性的。然而,使用这种新方法可以以良好的产率和出色的非对映选择性生产各种不对称的三取代和四取代环丁烷结构。该反应由任何可见光源促进,并且在用环境阳光照射时可以进行有效的克级环加成反应。