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
Nitroaldol-reaction of aldehydes in the presence of non-activated Mg:Al 2:1 hydrotalcite; a possible new mechanism for the formation of 2-aryl-1,3-dinitropropanes
Commercially available, non-activated 2:1 Mg:Al hydrotalcite catalyzes the nitroaldol reaction between a variety of aromatic and aliphatic aldehydes and simple nitroalkanes such as nitromethane and nitroethane. A new mechanism is proposed for the formation of the 1,3-dinitropropanes. The threo/erythro diastereoselectivity of the nitroethane-adducts was determined by 1H NMR spectroscopy and was found
Enantioselective Henry (nitroaldol) reaction catalyzed by axially chiral guanidines
作者:Hitoshi Ube、Masahiro Terada
DOI:10.1016/j.bmcl.2009.03.097
日期:2009.7
The enantioselective activation of nitroalkanes was attempted on the basis of the complexation between chiral guanidinium and nitronate through two hydrogen bonds. The proposed enantioselective activation was applied to the diastereo- and enantioselective Henry (nitroaldol) reaction of nitroalkanes with aldehydes using axiallychiral guanidine bases as the catalyst. Optically active nitroaldol products
Binaphthyl-Proline Hybrid Chiral Ligands: Modular Design, Synthesis, and Enantioswitching in Cu(II)-Catalyzed Enantioselective Henry Reactions
作者:Chao Yao、Yaoqi Chen、Chao Wang、Ruize Sun、Haotian Chang、Ruiheng Jiang、Lin Li、Xin Wang、Yue-Ming Li
DOI:10.1021/acs.joc.2c01127
日期:——
Chiral O–N–N tridentate ligands were designed from proline and BINOL. Their design strategy and performance were evaluated using a copper(II)-catalyzed asymmetric Henryreaction as a model. The desired β-nitroalcohols were obtained in up to 94% ee’s. Preliminary results suggested that the stereofacial selection of the reactions was mainly controlled by the chiral diamine moiety derived from proline
Chiral Mn(III)-salalen and -salan complexes derived from (S)-proline have been used as catalysts for the asymmetric Henry (nitro-aldol) reaction. We have also used this methodology for a variety of substrates to afford nitroaldol products in 40-94% yields with 25-92% ee.