1053174-35-8Relevant academic research and scientific papers
Asymmetric Michael addition of ketones to nitroolefins: Pyrrolidinyl-oxazole-carboxamides as new efficient organocatalysts
Kamal, Ahmed,Sathish, Manda,Srinivasulu, Vunnam,Chetna, Jadala,Chandra Shekar, Kunta,Nekkanti, Shalini,Tangella, Yellaiah,Shankaraiah, Nagula
, p. 8008 - 8018 (2014)
Chiral pyrrolidinyl-oxazole-carboxamides were synthesized and used as efficient new organocatalysts for the asymmetric Michael addition of ketones with nitroalkenes under solvent-free conditions. Gratifyingly, the corresponding Michael adducts were obtain
Pyrrolidine-carbamate based new and efficient chiral organocatalyst for asymmetric Michael addition of ketones to nitroolefins
Kaur, Amarjit,Singh, Kamal Nain,Sharma, Esha,Shilpy,Rani, Poonam,Sharma, Sandeep Kumar
, p. 6137 - 6143 (2018)
The novel ((S)-pyrrolidin-2-yl)methyl phenylcarbamate was synthesized and used as an efficient organocatalyst for the asymmetric Michael addition of cyclic/acyclic ketones to nitroolefins. Interestingly, the resulting Michael adducts were obtained in good to high yields (up to 96%) with excellent stereoselectivity (ee up to >99%, dr up to >99:1) without using any additive.
Enantiocomplementary synthesis of γ-nitroketones using designed and evolved carboligases
Garrabou, Xavier,Verez, Rebecca,Hilvert, Donald
, p. 103 - 106 (2017)
Artificial enzymes created by computational design and directed evolution are versatile biocatalysts whose promiscuous activities represent potentially attractive starting points for divergent evolution in the laboratory. The artificial aldolase RA9S.5-8, for example, exploits amine catalysis to promote mechanistically diverse carboligations. Here we report that RA95.5-8 variants catalyze the asymmetric synthesis of γ-nitroketones via two alternative enantiocomplementary Michael-type reactions: enamine-mediated addition of acetone to nitrostyrenes, and nitroalkane addition to conjugated ketones activated as iminium ions. In addition, a cascade of three aldolasecatalyzed reactions enables one-pot assembly of γ-nitroketones from three simpler building blocks. Together, our results highlight the chemical versatility of artificial aldolases for the practical synthesis of important chiral synthons.
(1R,2R)-(+)-(1,2)-DPEN-Bonded Sulfonic Acid Resin: A Trifunctional Heterogeneous Catalyst for Asymmetric Michael Additions of Acetone to Nitroolefins
Zhang, Chao,Li, Jing,Tian, Jun,Fang, Wangwang,Li, Yang,Chen, Ligong,Yan, Xilong
, p. 1248 - 1258 (2015)
Based on (1R,2R)-(+)-(1,2)-DPEN skeleton, a series of primary amine-sulfamide bifunctional catalysts were synthesized, which exhibited excellent catalytic performance in the Michael addition of acetone to β-nitrostyrene. Therefore, a trifunctional heterogeneous catalyst was designed and prepared by simple N-sulfonyl reaction of (1R,2R)-(+)-(1,2)-DPEN and sulfonyl chloride resin. It was employed for the aforementioned addition without any additive and satisfactory results (80.5% conversion; 84.3% ee) were obtained. Meanwhile, the structural and textural properties of the catalyst were characterized by infrared spectroscopy (FT-IR), elemental analysis, SEM, and N2 adsorption and desorption experiments. Finally, the generality of the catalyst was investigated.
Asymmetric Conjugate Addition of Nitroalkanes to Enones Using a Sulfonamide-Thiourea Organocatalyst
Kawada, Masahiro,Nakashima, Kosuke,Hirashima, Shin-Ichi,Yoshida, Akihiro,Koseki, Yuji,Miura, Tsuyoshi
, p. 6986 - 6991 (2017/07/15)
The asymmetric conjugate addition of nitroalkanes to α,β-unsaturated ketones in the presence of a catalytic amount of a novel sulfonamide-thiourea organocatalyst resulted in the corresponding γ-nitro carbonyl products in high yields with excellent enantio
Optically Active 4-Substituted 5-Nitropentan-2-ones: Valuable Chiral Building Blocks for the Stereocontrolled Construction of Spiro-Pyrazolone Scaffolds with Five Contiguous Stereogenic Centers
Sun, Jiao,Jiang, Cuiping,Zhou, Zhenghong
, p. 1165 - 1172 (2016/03/05)
The application of readily available optically active 4-substituted 5-nitropentan-2-ones as chiral building blocks in the stereocontrolled construction of spiro-pyrazolone scaffolds was investigated. In the presence of 1,8-diazabicyclo[5.4.0]undec-7-ene (
Highly Enantioselective Michael Addition of Nitroalkanes to Enones and Its Application in Syntheses of (R)-Baclofen and (R)-Phenibut
Guo, Xing-Tao,Shen, Jie,Sha, Feng,Wu, Xin-Yan
, p. 2063 - 2072 (2015/07/15)
A highly enantioselective Michael addition of nitroalkanes to α,β-unsaturated ketones was developed. In the presence of a chiral primary amine-thiourea catalyst based on dehydroabietic amine, γ-nitro ketones were obtained with excellent enantioselectiviti
Enantioselective addition of aryl ketones and acetone to nitroalkenes organocatalyzed by carbamate-monoprotected cyclohexa-1,2-diamines
Flores-Ferrndiz, Jess,Stiven, Alexander,Sotorros, Lia,Gmez-Bengoa, Enrique,Chinchilla, Rafael
, p. 970 - 979 (2015/09/01)
Enantiomerically pure carbamate-monoprotected trans-cyclohexane-1,2-diamines are used as chiral organocatalysts for the addition of aryl ketones and acetone to nitroalkenes to give enantioenriched β-substituted γ-nitroketones. The reaction was performed i
Asymmetric Michael addition of acetone to β-nitrostyrenes catalyzed by novel organocatalysts derived from D-isomannide or Lisoidide
Chen, Ling-Yan,Guillarme, Stephane,Whiting, Andrew,Saluzzo, Christine
, p. 215 - 227 (2014/05/20)
Novel bifunctional organocatalysts were prepared from D-isomannide or L-isoidide in three steps. These catalysts were then evaluated in the asymmetric Michael addition of acetone to trans-.-nitrostyrenes. Although moderate enantioselectivities were observed, this study has highlighted that a simple chiral primary diamine can catalyze this reaction. Furthermore, the reaction was also performed with an isomannide-derived diimine which was transformed in situ into the active catalyst under acidic conditions leading to the best enantioselectivity. ARKAT-USA, Inc.
New simple primary amine-thiourea organocatalysts and their application in asymmetric conjugate addition
Yu, Lu,Li, Pengfei
supporting information, p. 3697 - 3700 (2014/06/23)
A kind of simple primary amine-thiourea organocatalysts was developed. And their application in asymmetric conjugate addition of ketone to nitroalkene was investigated. In the presence of the new primary amine-thiourea, the conjugate addition of ketone to
