- Water-Mediated Intramolecular Cyclization/Oxidation of α-Carbonyl Sulfur Ylides: Synthesis of Corey-Chaykovsky Reagent Type Heterocycles
-
A new class of Corey-Chaykovsky reagent type five-membered heterocycles with an oxosulfonium ylide moiety has been synthesized by the water-mediated intramolecular cyclization/oxidation of α-carbonyl sulfur ylides generated in situ from sulfonium salts under mild conditions.
- Kang, Xiaokang,Liang, Xiayu,Zeng, Qingle
-
supporting information
p. 7477 - 7481
(2021/10/12)
-
- Synthesis of Isoxazolines from Nitroalkanes via a [4+1]-Annulation Strategy
-
A novel access to isoxazolines was developed using the [4+1]-annulation of α-keto-stabilized sulfur ylides with N,N-bis(siloxy)enamines derived from aliphatic nitro compounds. The resulting 5-keto-substituted isoxazolines were shown to be convenient precursors of polysubstituted 3-hydroxypyrrolidines via the one-pot catalytic N?O hydrogenolysis/intramolecular reductive amination sequence. Application of this approach to the formal synthesis of Merck's potent NK1 receptor antagonist was demonstrated. (Figure presented.).
- Ushakov, Pavel Yu.,Khatuntseva, Elizaveta A.,Nelyubina, Yulia V.,Tabolin, Andrey A.,Ioffe, Sema L.,Sukhorukov, Alexey Yu.
-
supporting information
p. 5322 - 5327
(2019/11/13)
-
- Catalyst-Free Synthesis of 2,3-Dihydrobenzofurans via a Formal [4+1] Annulation of Propargylamines with Sulfur Ylides
-
A simple, general route to the 2,3-dihydrobenzofurans substituted at C3 by an aryethynyl or aryl group, starting from propargylamine and its derivatives with benzoyl sulfonium salts, has been developed. This reaction involved an in situ generated o-quinone methide (o-QM) intermediate followed by [4+1] annulation with sulfur ylides. Notably, this protocol's features include moderate to excellent yields and remarkable diastereoselectivity (>20:1 dr in general), easy performance, as well as applicability to versatile 2,3-dihydrobenzofurans with aryethynyl or an aryl group via C-C and C-O bond formation in one pot without any catalyst in an aqueous mixed solvent.
- He, Xinwei,Xie, Mengqing,Tang, Qiang,Zuo, Youpeng,Li, Ruxue,Shang, Yongjia
-
p. 11623 - 11638
(2019/10/02)
-
- Synthesis of functionalized thietanes via electrophilic carbenoid-induced ring expansion of thiiranes with sulfonium acylmethylides as carbene precursors
-
Various functionalized thietanes were prepared from thiiranes via an electrophilic ring expansion with rhodium carbenoids as electrophiles generated from safe and readily accessible dimethylsulfonium acylmethylides. The reaction appears to proceed through electrophilic metallocarbenoid-induced activation of thiiranes, nucleophilic ring-opening of the activated thiiranes with dimethyl sulfide as a transient nucleophile, and nucleophilically intramolecular cyclization. The Umpolung from the nucleophilic ylides to the electrophilic carbenoids plays an important role in both the activation and ring opening of thiiranes and subsequent cyclization. The current method provides a new strategy for the efficient preparation of functionalized thietanes from readily available thiiranes.
- Dong, Jun,Du, Hongguang,Xu, Jiaxi
-
p. 10724 - 10739
(2019/09/30)
-
- 1,6-Conjugated Addition-Mediated [2+1] Annulation: Approach to Spiro[2.5]octa-4,7-dien-6-one
-
A formal 1,6-conjugated addition-mediated [2+1] annulation to synthesize spiro[2.5]octa-4,7-dien-6-one with p-quinone methides and sulfur ylides has been described. This domino-type process was highly diastereoselective and exhibited good functional group tolerance and scalability without the use of metals and bases.
- Yuan, Zhenbo,Fang, Xinxin,Li, Xuanyi,Wu, Jie,Yao, Hequan,Lin, Aijun
-
p. 11123 - 11130
(2015/11/18)
-
- Functionalized α-keto stabilized sulfonium ylides as highly active ligand precursors for palladium catalyzed Suzuki-Miyaura cross-couplings
-
Five α-keto stabilized sulfonium ylides as type (Me) 2SCHC(O)C6H4-p-X (X = H, Br, NO2, CH3 and OCH3) {L1-L5} were used as ligand precursors in the Suzuki-Miyaura cross-coupling reaction. The best catalytic performance was obtained by using a sulfonium ylide/Pd ratio of 2:1. The catalytic systems displayed high activities, which increased in the order R = NO2 (L3) 2) 1) 3 (L4) 3 (L5). The coupling reactions proceeded smoothly with 0.05 mol% PdCl2 and 0.1 mol% L5 in DMF at 130 °C between varieties of electronically activated, deactivated and neutral aryl halides and aryl boronic acids within short reaction times and without the need for exclusion of air which gave good to high yields of the corresponding products. All the studied ligands demonstrated very high activity in the Suzuki-Miyaura cross-coupling, which yielded turnover numbers up to 1940. Comparative studies showed that the performance of sulfonium ylide L5 is significantly superior to that of related phosphine-free ligands.
- Sabounchei, Seyyed Javad,Hashemi, Ali
-
p. 123 - 127
(2014/08/18)
-
- Synthesis and characterization of novel simultaneous C and O-coordinated and nitrate-bridged complexes of silver(i) with carbonyl-stabilized sulfonium ylides and their antibacterial activities
-
Reaction of sulfonium ylides (Me)2SCHC(O)C6H 4R (R = H; m-NO2; p-NO2; p-OMe; p-Me and p-Br) with AgNO3 in dichloromethane leads to various compounds. Single crystal X-ray diffraction analysis reveals that the adducts take 3 forms: (i) two-dimensional polymer, [AgNO3(Me2SCHC(O)C 6H5)]n (1), with nitrate bridges in which each nitrate coordinates to three silver atoms through two oxygen atoms and two Me2SCHC(O)C6H5 ligands coordinate to silver centers through carbon atoms; (ii) cationic binuclear, [Ag(Me 2SCHC(O)C6H4-m-NO2) 2]2(NO3)2·2H2O (2), in which Me2SCHC(O)C6H4-m-NO2 ligands simultaneously coordinate through both carbon and oxygen atoms with nitrate as a counter ion, and (iii) cationic mononuclear and anionic binuclear, [Ag(Me2SCHC(O)C6H4-p-NO2) 2]2[{AgNO3(μ-NO3) (Me 2SCHC(O)C6H4-p-NO2)} 2]·2CH3OH (3), in which nitrate groups act as bridging as well as terminal ligands, and Me2SCHC(O)C 6H4-p-NO2 ligands display C-coordination. Characterization of the obtained compounds was also performed by infrared, 1H- and 13C-NMR spectroscopy and analytical data indicated a 1:2 stoichiometry between the silver(i) nitrate and ylide p-OMe (4) and 1:1 for ylides p-Me (5) and p-Br (6). In addition, the antibacterial effects of DMSO-solutions of complexes 1-6 were evaluated by the agar disc diffusion method against three Gram positive and three Gram negative bacteria. All complexes displayed antibacterial activity against these bacteria, with high levels of inhibitory potency exhibited against the Gram negative species.
- Sabounchei, Seyyed Javad,Akhlaghi Bagherjeri, Fateme,Mozafari, Zeinab,Boskovic, Colette,Gable, Robert W.,Karamian, Roya,Asadbegy, Mostafa
-
supporting information
p. 2520 - 2529
(2013/04/10)
-
- Preparation of chiral cyclopropanes with a carbohydrate fragment from levoglucosenone
-
Levoglucosenone (a chiral α,β-unsaturated ketone derivative of cellulose) underwent stereoselective cyclopropanation with sulfonium ylides to form chiral trisubstituted cyclopropanes annulated with the carbohydrate moiety in high yields.
- Samet, Alexander V.,Shestopalov, Anatolly M.,Lutov, Dmitriy N.,Rodinovskaya, Lyudmila A.,Shestopalov, Alexander A.,Semenov, Victor V.
-
p. 1986 - 1989
(2008/02/13)
-