We report the design and synthesis of a new series of binaphthol based chiral organocatalysts which can act as metal-free organocatalysts in the enantioselective Henry reaction with very good yield and ee.
Enantioselective Henry reaction catalyzed by copper(II)—Cinchona alkaloid complexes
作者:Mariola Zielińska-Błajet、Jacek Skarżewski
DOI:10.1016/j.tetasy.2011.02.003
日期:2011.2
An enantioselective Henry reaction was efficiently carried out under mild reaction conditions in the presence of catalytic 9-epi and natural Cinchonaalkaloids and copper (II) acetate. The best catalytic performance was observed for native quinine (12 mol %) and Cu(OAc)2 (10 mol %). Aromatic and aliphatic aldehydes with nitromethane and its α-substituted derivatives provided the corresponding β-nitroalcohols
Efficient Asymmetric Copper(I)-Catalyzed Henry Reaction Using Chiral N-Alkyl-C1-tetrahydro-1,1′-bisisoquinolines
作者:Yao Qiong ji、Gao Qi、Zaher M. A. Judeh
DOI:10.1002/ejoc.201100579
日期:2011.7.14
closely related chiral N-alkyl-C1-tetrahydro-1,1′-bisisoquinoline ligands only differing in the steric bulk of the alkyl groups has been examined in the asymmetricHenry reaction. A complex derived from the (R)-N-methyl-1′,2′,3′,4′-tetrahydro-1,1′-bisisoquinoline and copper(I) chloride proved to be a very efficient catalyst system that can promote the reaction of a wide range of aromatic and aliphatic
Novel bifunctional catalysts having guanidine and thiourea functional groups were developed for the asymmetric Henry (nitroaldol) reaction. Various structural developments of the catalyst revealed that the compound having an octadecyl-substituted guanidine and thiourea groups linked with a chiral spacer derived from phenylalanine, i.e., 1e, efficiently promoted the Henry reaction. This bifunctional
Copper Complex of Aminoisoborneol Schiff Base Cu
<sub>2</sub>
(SBAIB‐d)
<sub>2</sub>
: An Efficient Catalyst for Direct Catalytic Asymmetric Nitroaldol (Henry) Reaction
new bifunctional coppercomplex of the aminoisoborneolSchiffbase – Cu2(SBAIB‐d)2 – has been developed for the effective directcatalyticasymmetricHenryreaction. One mol% of this catalyst produces the expected Henry products in high yields (up to 99%) with excellent enantioselectivities (up to 98% ee). The utility of the present catalyst was also extended to the Henryreaction with nitroethane