AbstractThis study reports on the thiourea dioxide catalyzed transferhydrogenation of diverse C=N–containing heterocyclic compounds with Hantzsch ester as the hydrogen source. With this cost effective and readily available catalyst, a wide range of 2-substituted quinolines, 3-substituted-2H-1,4-benzoxazines and 3-substituted-2H-1,4-benzothiazines were efficiently reduced to the corresponding tetrahydroquinolines
Ir-Catalyzed Enantioselective Hydrogenation of 2<i>H</i>-1,4-Benzoxazines with a Chiral 1,2,3,4-Tetrahydro-1-naphthylamine Derived Phosphine-aminophosphine Ligand
作者:Juan Hu、Daoyong Wang、Zhuo Zheng、Xiangping Hu
DOI:10.1002/cjoc.201200944
日期:2012.11
Unsymmetrical hybrid chiral phosphine‐aminophosphine ligandderived from 1,2,3,4‐tetrahydro‐1‐naphthylamine has been found to be highly efficient in the Ir‐catalyzed asymmetric hydrogenation of various 3‐aryl‐2H‐1,4‐benzoxazines, providing good enantioselectivities (up to 95% ee) and high catalytic activity (S/C up to 5000).
已发现衍生自1,2,3,4-四氢-1-萘胺的不对称杂化手性膦-氨基膦配体在各种3-芳基-2 H -1,4-苯并恶嗪的Ir催化不对称氢化中非常有效,提供良好的对映选择性(高达95%ee)和高催化活性(S / C高达5000)。
Synthesis of Dihydrobenzoheterocycles through Al(OTf)<sub>3</sub>-Mediated Cascade Cyclization and Ionic Hydrogenation
A facile and versatile synthesis of dihydrobenzoheterocycles via Al(OTf)(3)-mediated cascade cyclization and ionic hydrogenation has been developed. The reaction is applicable to a wide range of substrates with various functional groups to afford the corresponding products in good yields.