Results 51 to 60 of about 2,777 (221)

Organocatalytic Formal (3+2+1)‐Cycloaddition of Allenoates, Michael Acceptors, and Carbaldehydes

Chemistry – A European Journal, EarlyView.
The use of secondary amine Lewis base organocatalysts allows for the unprecedented activation of allenoates for formal (3+2+1)‐cycloadditions with Michael acceptors and aromatic carbaldehydes. ABSTRACT Employing secondary amines as covalently interacting Lewis basic organocatalysts allows for the activation of electron‐deficient allenes (allenoates ...
David Naderer, Alexander Pötscher, Katharina Eder, Uwe Monkowius, Markus Himmelsbach, Mario Waser   +5 more
wiley   +1 more source

Enantioselective Organocatalytic Michael Addition of Malonates to α,β-Unsaturated Ketones

, 2016
A novel type of primary amine thiourea organocatalysts derived from 1,2-diaminocyclohexane and 9-amino (9-deoxy) cinchona alkaloid was developed into asymmetric Michael addition of malonates to enones.
Qiaoxia Liu (2394481), Xinmiao Liang (316448), Shigang Wen (1672489), Yongcan Wang (2394484), Wenjun Li (41954), Jinxing Ye (1376925), Feng Yu (273443), Pengfei Li (290581)   +7 more
core   +1 more source

Oxidative Generation and Reactivity of the Cyclopropyl Radical From a Martin Silicate

Chemistry – A European Journal, EarlyView.
A photoredox strategy employing Martin silicates enables the oxidative generation and controlled capture of cyclopropyl radicals, including the naked one, long considered challenging intermediates. The method affords functionalized cyclopropanes through both Giese‐type additions and dual nickel/photoredox C(sp3)−C(sp2) cross‐couplings.
Amal Lakhal, Alexandre Millanvois, Louis Fensterbank, Cyril Ollivier   +3 more
wiley   +1 more source

On the Metabolism of Malonate and Malonate Decarboxylase Activity in Pseudomonas sp.

Journal of the agricultural chemical society of Japan, 1974
1. Ps. avalis IAM 1177およびPs. fluorescens AT CC 11250を用いて,マロン酸脱炭酸酵素について検討した. 2. 供試菌は培地中に著量の炭酸ガスを放出しながら,マロン酸を炭素源としてよく利用した.菌体にとり込まれたマロン酸の炭素は,他の菌体成分にくらべていちじるしく高く脂質区分に検出された. 3. マロン酸脱炭酸酵素はマロン酸によって誘導されグルコースやリンゴ酸などの炭素源によって強く抑制された.また,メチルマロン酸およびエチルマロン酸にも弱い誘導作用が認められた. 4. Ps. avalisから約16倍に部分精製した酵素標品では,マロン酸のほかにメチルマロン酸が基質となることが認められた. 5.
TAKAMURA, Yoshichika, TOMIOKA, Ikuo, SOEJIMA, Masami   +2 more
openaire   +2 more sources

Enantioselective Organocatalytic Michael Addition of Malonates to alpha,beta-Unsaturated Ketones

, 2009
A novel type of primary amine thiourea organocatalysts derived from 1,2-diaminocyclohexane and 9-amino (9-deoxy) cinchona alkaloid was developed into asymmetric Michael addition of malonates to enones.
Yu, Feng, Wen, Shigang, Li, Wenjun, Liang, Xinmiao, Wang, Yongcan, Liu, Qiaoxia, Li, Pengfei, Ye, Jinxing   +7 more
core   +1 more source

Nitrooxylation in Organic Synthesis: From Classical Nitrate Ester Formation to Modern Catalytic Strategies

Chemistry – A European Journal, EarlyView.
Nitrooxylation—the installation of nitrate esters (–ONO2) has evolved from classical mixed‐acid protocols to catalytic and mechano‐, flow‐, photo‐, and electrochemical strategies. This review delineates ionic and radical manifolds for C–ONO2 bond formation, emphasizing mechanistic control, selected substrate scope, and selectivity.
Jayanta Dey, Dmitry Katayev
wiley   +1 more source

Enantioselective Michael Addition of Malonates to Chalcone Derivatives Catalyzed by Dipeptide-derived Multifunctional Phosphonium Salts

, 2016
Highly enantioselective Michael addition of malonates to enones catalyzed by dipeptide-derived multifunctional phosphonium salts has been developed. The newly established catalytic system was characterized with its wide substrate scope featured with ...
Gang Zhao (161405), Jiaxing Zhang (363434), Hongyu Wang (366946), Guosheng Fang (3195486), Changwu Zheng (1699954), Dongdong Cao (350033)   +5 more
core   +1 more source

Cross‐Dehydrogenative Coupling Reactions With Redox‐Active Guanidine Reagents

Chemistry – A European Journal, EarlyView.
ABSTRACT Cross‐dehydrogenative coupling (CDC) reactions are attractive and environmentally friendly ways to form new C‐C and other element‐element bonds. Here, we report the first CDC reactions triggered by a redox‐active guanidine reagent. N‐phenyltetrahydroisoquinoline and derivatives with electron‐donating and withdrawing substituents at the N ...
Petra Walter, Olaf Hübner, Hans‐Jörg Himmel   +2 more
wiley   +1 more source

An Investigation Into the Yields of 3,4‐Methylenedioxyphenyl‐2‐propanone (MDP2P) From Glycidate Pre‐Precursors

Drug Testing and Analysis, EarlyView.
Hydrolysis of the glycidate pre‐precursors MMDMG and EMDMG was evaluated for MDP2P production. Acid hydrolysis of MMDMG (HCl, 100°C, 18 h) yielded the highest MDP2P recovery (79%), whereas base hydrolysis produced only slightly lower yields (73%), demonstrating both pathways are effective routes to this key MDMA precursor.
Alexandra L. Mercieca, Ella S. Schuett, Andrew M. McDonagh, Shanlin Fu, Morgan Alonzo   +4 more
wiley   +1 more source

Base‐Free Nickel‐Catalyzed Three‐Component Coupling of Aldehydes, Butadiene, and Malonate Derivatives: Toward Sustainable Synthesis of Highly Functionalized Molecules

European Journal of Organic Chemistry, EarlyView.
A nickel‐catalyzed three‐component reaction between arylaldehydes, butadiene, and malonates is developed yielding high functionalized homoallylic alcohols in a single step. No additional base is required and the reaction shows broad substrates compatibility with yields up to 96% and an exclusive selectivity toward the linear E‐isomer.
Anthony Saint Pol, Radhouan Maazaoui, Céline Delabre, Laëtitia Chausset‐Boissarie, Maël Penhoat, Isabelle Suisse, Aurélien Béthegnies, Mathieu Sauthier   +7 more
wiley   +1 more source