37129-42-3Relevant academic research and scientific papers
Discovery of Oxygen α-Nucleophilic Addition to α,β-Unsaturated Amides Catalyzed by Redox-Neutral Organic Photoreductant
Luan, Zi-Hong,Qu, Jian-Ping,Kang, Yan-Biao
, p. 20942 - 20947 (2020)
The conjugate additions of oxygen-centered nucleophiles to conjugate acceptors are among the most powerful C-O bond formation reactions. The conjugate addition normally takes place at the β-position carbon to the electron-withdrawing group, resulting in the formation of a stabilized carbanion intermediate that can be quenched by proton or electrophiles to form the β-addition (i.e., hetero-Michael addition) products. On the contrary, the formation of α-hydroxyl or alkoxyl amides through conjugate addition needs an α,β-inverse addition. Nevertheless, a regio-inversed nucleophilic α-addition of oxygen-centered nucleophiles to α,β-unsaturated carbonyl compounds still remains less explored because of the electronic mismatch. In this research, we discovered the first α-specific nucleophilic addition of α,β-unsaturated amides with oxygen and fluoride nucleophiles. This region-inversed nucleophilic addition is enabled by the catalysis of a novel redox-neutral nondonor-acceptor organic photoreductant (CBZ6). As low as 0.5 mol % of visible light photoreductant was employed. The mechanistic insights were also explored. The oxidative potential of the excited state of CBZ6 is obtained in -1.92 V (vs SCE), presenting a stronger reductive potential than representative metal-cored or organic photoredox catalysts. This feature enabled the umpolung of α,β-unsaturated amides to take place α-nucleophilic addition other than the normal β-addition.
Transition-metal-free α-arylation of oxindoles: Vi a visible-light-promoted electron transfer
Liang, Kangjiang,Li, Na,Zhang, Yang,Li, Tao,Xia, Chengfeng
, p. 3049 - 3053 (2019/03/13)
An operationally simple photochemical strategy for the direct arylation of oxindoles with (hetero)aryl halides in the absence of both transition metals and photoredox catalysts has been developed. The reaction provides an efficient way to construct various 3-aryloxindole building blocks of pharmaceutical interest at ambient temperature by using household compact fluorescent light (CFL) bulbs as the light source. Preliminarily, mechanistic studies revealed that the intermolecular electron transfer relied on the formation of photon-absorbing electron-donor-acceptor (EDA) complexes between electron-rich oxindole enolates and electron-deficient (hetero)aryl halides, and a radical chain mechanism was operative.
PURINE INHIBITORS OF HUMAN PHOSPHATIDYLINOSITOL 3-KINASE DELTA
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Page/Page column 84-85, (2017/11/01)
The instant invention provides compounds of formula (I) which are PI3K-delta inhibitors, and as such are useful for the treatment of PI3K-delta-mediated diseases such as inflamation, asthma, COPD and cancer.
An asymmetric pericyclic cascade approach to 3-alkyl-3-aryloxindoles: Generality, applications and mechanistic investigations
Richmond, Edward,Ling, Kenneth B.,Duguet, Nicolas,Manton, Lois B.,elebi-?lcüm, Nihan,Lam, Yu-Hong,Alsancak, Sezen,Slawin, Alexandra M. Z.,Houk,Smith, Andrew D.
supporting information, p. 1807 - 1817 (2015/02/19)
The reaction of L-serine derived N-arylnitrones with alkylarylketenes generates asymmetric 3-alkyl-3-aryloxindoles in good to excellent yields (up to 93%) and excellent enantioselectivity (up to 98% ee) via a pericyclic cascade process. The optimization, scope and applications of this transformation are reported, alongside further synthetic and computational investigations. The preparation of the enantiomer of a Roche anti-cancer agent (RO4999200) 1 (96% ee) in three steps demonstrates the potential utility of this methodology.
Regiodivergent access to five- and six-membered benzo-fused lactams: Ru-catalyzed olefin hydrocarbamoylation
Li, Bin,Park, Yoonsu,Chang, Sukbok
, p. 1125 - 1131 (2014/02/14)
We report herein a new strategy of the Ru-catalyzed intramolecular olefin hydrocarbamoylation for the regiodivergent synthesis of five- and six-membered benzo-fused lactams starting from N-(2-alkenylphenyl)formamides. Using a combined catalyst of Ru3
Chiral scandium(III)-catalyzed enantioselective α-arylation of N-unprotected 3-substituted oxindoles with diaryliodonium salts
Guo, Jing,Dong, Shunxi,Zhang, Yulong,Kuang, Yulong,Liu, Xiaohua,Lin, Lili,Feng, Xiaoming
supporting information, p. 10245 - 10249 (2013/10/21)
Catalytic asymmetric α-arylation of N-unprotected 3-substituted oxindoles with diaryliodonium salts has been realized by a chiral Lewis acid promoted electrophilic addition and aryl-rearrangement process. Single C3-arylated products containing a quaternary carbon center were generated in high enantioselectivity and reactivity. Copyright
Pericyclic cascade with chirality transfer: Reaction pathway and origin of enantioselectivity of the hetero-claisen approach to oxindoles
Celebi-Oelcuem, Nihan,Lam, Yu-Hong,Richmond, Edward,Ling, Kenneth B.,Smith, Andrew D.,Houk, Kendall N.
, p. 11478 - 11482 (2012/01/06)
A new pericyclic cascade is proposed for the chiral auxiliary-controlled synthesis of 3,3-disubstituted oxindoles from nitrones and ketenes. The remarkable acyclic 1,6-stereochemical induction, hitherto unexplained, is rationalized by a stereoselective 3+
