862907-06-0Relevant articles and documents
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.
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.
Iron(iii)-salan complexes catalysed highly enantioselective fluorination and hydroxylation of β-keto esters and N-Boc oxindoles
Gu, Xin,Zhang, Yan,Xu, Zhen-Jiang,Che, Chi-Ming
, p. 7870 - 7873 (2014/07/08)
Chiral iron(iii)-salan complexes catalysed highly enantioselective α-fluorination and α-hydroxylation of β-keto esters and N-Boc oxindoles to give the corresponding products in high yields and good-to-excellent ee values under mild reaction conditions. This journal is the Partner Organisations 2014.
Chincona alkaloid-catalyzed enantioselective trifluoromethylthiolation of oxindoles
Yang, Tao,Shen, Qilong,Lu, Long
, p. 678 - 680 (2014/10/16)
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
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
, 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.
Facile synthesis of enantioenriched Cγ-tetrasubstituted α-amino acid derivatives via an asymmetric nucleophilic addition/protonation cascade
Duan, Shu-Wen,An, Jing,Chen, Jia-Rong,Xiao, Wen-Jing
, p. 2290 - 2293 (2011/06/22)
Chemical equations presented. An asymmetric nucleophilic addition/protonation reaction of 3-substituted oxindoles and ethyl 2-phthalimidoacrylate has been described. This strategy can give direct access to Cγ-tetrasubstituted α-amino acid derivatives bearing 1,3-nonadjacent stereocenters with up to 98% yield, 94:6 dr, and >99% ee. Dual activation is proposed in the transition state, and the opposite enantiomers can be obtained simply by changing cinchonidine-derived catalyst to the cinchonine analogue.
Catalytic enantioselective fluorination of oxindoles
Hamashima, Yoshitaka,Suzuki, Toshiaki,Takano, Hisashi,Shimura, Yuta,Sodeoka, Mikiko
, p. 10164 - 10165 (2007/10/03)
We have developed a highly efficient catalytic enantioselective fluorination of oxindole derivatives. In the presence of a catalytic amount of chiral Pd complex 2 (2.5 mol %), various substrates, including aryl- and alkyl-substituted oxindoles, were fluor
