1175713-08-2Relevant academic research and scientific papers
Chincona alkaloid-catalyzed enantioselective trifluoromethylthiolation of oxindoles
Yang, Tao,Shen, Qilong,Lu, Long
, p. 678 - 680 (2014)
An organocatalytic asymmetric trifluoromethylthiolation of 3-aryl or 3-alkyloxindoles employing a trifluoromethyl-substituted thioperoxide as the electrophilic trifluoromethylthiolating reagent was described. Reactions occurred in good to excellent enanti
The catalytic decarboxylative allylation of enol carbonates: The synthesis of enantioenriched 3-allyl-3′-aryl 2-oxindoles and the core structure of azonazine
Babu, K. Naresh,Bisai, Alakesh,Khatua, Arindam,Pal, Souvik,Roy, Avishek
, p. 127 - 131 (2021/12/29)
The catalytic asymmetric synthesis of 3-allyl-3′-aryl 2-oxindoles has been shownviathe Pd(0)-catalyzed decarboxylative allylation of allylenol carbonates. This methodology provides access to a variety of 2-oxindole substrates (5a-v) with all-carbon quater
Organocatalytic stereoselective conjugate addition of 3-substituted oxindoles with in situ generated ortho-quinone methides
Liang, Weihong,Yin, Wenhao,Wang, Tingzhong,Qiu, Fayang G.,Zhao, Junling
, p. 1742 - 1747 (2018/04/02)
A novel method for the stereoselective conjugate addition of 3-substituted oxindoles to in situ generated o-QMs was described. This process was catalyzed efficiently by a cinchonidine-derived squaramide catalyst in oil-water phase, furnishing the corresponding 3,3-disubsituted oxindole derivatives in moderate to high yields (up to 98%) with high stereoselectivities (up to 95% ee, 15.4:1 dr). The utility of this reaction was also investigated by the gram-scale synthesis and derivatization of one of the products.
Enantioselective construction of tetrasubstituted stereogenic carbons through bronsted base catalyzed michael reactions: α′-hydroxy enones as key enoate equivalent
Badiola, Eider,Fiser, Bla,Gmez-Bengoa, Enrique,Mielgo, Antonia,Olaizola, Iurre,Urruzuno, Iaki,Garca, Jess M.,Odriozola, Jos M.,Razkin, Jess,Oiarbide, Mikel,Palomo, Claudio
supporting information, p. 17869 - 17881 (2015/02/19)
Catalytic and asymmetric Michael reactions constitute very powerful tools for the construction of new C-C bonds in synthesis, but most of the reports claiming high selectivity are limited to some specific combinations of nucleophile/electrophile compound types, and only few successful methods deal with the generation of all-carbon quaternary stereocenters. A contribution to solve this gap is presented here based on chiral bifunctional Bronsted base (BB) catalysis and the use of α′-oxy enones as enabling Michael acceptors with ambivalent H-bond acceptor/donor character, a yet unreported design element for bidentate enoate equivalents. It is found that the Michael addition of a range of enolizable carbonyl compounds that have previously demonstrated challenging (i.e., α-substituted 2-oxindoles, cyanoesters, oxazolones, thiazolones, and azlactones) to α′-oxy enones can afford the corresponding tetrasubstituted carbon stereocenters in high diastereo- and enantioselectivity in the presence of standard BB catalysts. Experiments show that the α′-oxy ketone moiety plays a key role in the above realizations, as parallel reactions under identical conditions but using the parent α,β-unsaturated ketones or esters instead proceed sluggish and/or with poor stereoselectivity. A series of trivial chemical manipulations of the ketol moiety in adducts can produce the corresponding carboxy, aldehyde, and ketone compounds under very mild conditions, giving access to a variety of enantioenriched densely functionalized building blocks containing a fully substituted carbon stereocenter. A computational investigation to rationalize the mode of substrate activation and the reaction stereochemistry is also provided, and the proposed models are compared with related systems in the literature.
In situ generation of electrophilic trifluoromethylthio reagents for enantioselective trifluoromethylthiolation of oxindoles
Zhu, Xing-Li,Xu, Jin-Hui,Cheng, Dao-Juan,Zhao, Li-Jiao,Liu, Xin-Yuan,Tan, Bin
, p. 2192 - 2195 (2014/05/06)
An organocatalytic asymmetric trifluoromethylthiolation reaction via in situ generation of active electrophilic trifluoromethylthio species involving trichloroisocyanuric acid and AgSCF3 as a practical and easily handled electrophilic SCF3 source for CSP 3-SCF3 bond formation was developed. Reactions with this one-pot version strategy occurred in good yields and excellent stereoselectivities to access enantiopure oxindoles bearing a SCF 3-substituted quaternary chiral center. The straightforward process described here makes use of simple starting materials and proceeds under mild conditions, which will be useful in medicinal chemistry and diversity-oriented syntheses.
