First Iridium-Catalyzed Highly Enantioselective Hydrogenation of β-Nitroacrylates
摘要:
The first highly chemo- and enantioselective hydrogenation of beta-nitroacrylates was accomplished with an iridium catalyst (Ir-4) with yields and enantioselectivities of up to 96% and 98% ee, respectively. The resulting alpha chiral beta-nitro propionates are attractive building blocks for the synthesis of chiral beta(2)-amino acids, which are the core scaffolds of bioactive natural products, pharmaceuticals, and beta-peptides.
First Iridium-Catalyzed Highly Enantioselective Hydrogenation of β-Nitroacrylates
摘要:
The first highly chemo- and enantioselective hydrogenation of beta-nitroacrylates was accomplished with an iridium catalyst (Ir-4) with yields and enantioselectivities of up to 96% and 98% ee, respectively. The resulting alpha chiral beta-nitro propionates are attractive building blocks for the synthesis of chiral beta(2)-amino acids, which are the core scaffolds of bioactive natural products, pharmaceuticals, and beta-peptides.
optimized an enantioselective Michael reaction of malononitrile with β,β‐disubstituted nitroalkenes. This reaction was catalyzed by a cinchona alkaloid derived thiourea catalyst, producing products of high yields (up to 98 %) and stereoselectivities (up to 93 % ee). One of the adducts was used as an intermediate for the synthesis of dihydropyrrole derivative bearing a synthetically valuable quaternary chiral
Copper-Catalyzed Cross-Dehydrogenative Coupling of α-Hydroxy Esters with Nitromethane
作者:Jin Jiang、Lili Xiao
DOI:10.1055/a-1539-9116
日期:2021.11
β-nitro-α-hydroxy esters were prepared via cross-dehydrogenative coupling reaction using α-hydroxy esters as hydroxy compounds and nitromethane as a nucleophile. The reaction is believed to undergo an oxidation of the hydroxygroup and then an addition of the generated carbonyl group. It is an example of CDC reactions related to hydroxy compounds via carbonyl intermediates.
Enantioselective addition of nitromethane to α-keto esters catalyzed by copper(<scp>ii</scp>)–iminopyridine complexes
作者:Gonzalo Blay、Victor Hernández-Olmos、José R. Pedro
DOI:10.1039/b716446g
日期:——
The coppercomplex of a chiral iminopyridine easily prepared from (R)-(-)-fenchone and picolylamine catalyzes the enantioselective Henry (nitroaldol) reaction between nitromethane and alpha-keto esters. Good yields and modest to good enantioselectivities are obtained for a wide range of alpha-keto esters, bearing aromatic, alkyl or alkenyl groups attached to the ketone carbonyl group.
Organocatalytic Asymmetric Transferhydrogenation of β-Nitroacrylates: Accessing β<sup>2</sup>-Amino Acids
作者:Nolwenn J. A. Martin、Xu Cheng、Benjamin List
DOI:10.1021/ja8069852
日期:2008.10.22
We describe a highly efficient and enantioselective Hantzsch ester mediated conjugate reduction of beta-nitroacrylates that is catalyzed by a Jacobsen thiourea catalyst as a key step in a new route to optically active beta2-amino acids.