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排序方式: 共有159条查询结果,搜索用时 15 毫秒
1.
Peña D López F Harutyunyan SR Minnaard AJ Feringa BL 《Chemical communications (Cambridge, England)》2004,(16):1836-1837
Highly enantioselective Cu-catalysed 1,4-addition of diphenylzinc to cyclohexenone has been achieved for the first time using a monodentate phosphoramidite ligand. 相似文献
2.
Vyskocil S Meca L Tislerová I Císarová I Polásek M Harutyunyan SR Belokon YN Stead RM Farrugia L Lockhart SC Mitchell WL Kocovský P 《Chemistry (Weinheim an der Bergstrasse, Germany)》2002,8(20):4633-4648
The title binaphthyls 19 and 26, which are the positional isomers of 2-methoxy-2'-(diphenylphosphino)-1,1'-binaphthyl (MOP, 19) and 2-amino-2'-hydroxy-1,1'-binaphthyl (NOBIN, 26), have been synthesized by Suzuki coupling as the key step (10 + 15-->18), followed by functional group transformations, involving C-P and C-N bond formation (18-->19 and 18-->23). Racemic intermediate 22 was resolved by co-crystallization with N-benzylcinchonidinium chloride and the absolute configuration determined by X-ray crystallography. These novel binaphthyls are configurationally stable and, as such, potentially usable as chiral ligands in asymmetric reactions. Michael addition of the glycine-derived enolate 40 to methyl acrylate, carried out in the presence of (R)-(-)-27 as the chiral phase-transfer catalyst, afforded L-glutamic acid (S)-(+)-43 of 92% ee (after hydrolysis of the primary product). 相似文献
3.
A. S. Saghiyan A. V. Geolchanyan L. L. Manasyan G. M. Mkrtchyan N. R. Martirosyan S. A. Dadayan T. V. Kochickyan V. S. Harutyunyan A. A. Avetisyan V. I. Tararov V. I. Maleev Yu. N. Belokon' 《Russian Chemical Bulletin》2004,53(4):932-935
An efficient method was developed for the asymmetric synthesis of (R)-S-(1,2,4-triazol-3-yl)cysteines by the addition of 3,4-disubstituted 1,2,4-triazole-5-thiols at the electrophilic C=C bond in a NiII complex of a Schiff base of dehydroalanine with (S)-N-(N-benzylprolyl)aminobenzophenone. The stereoselectivity of the formation of diastereomeric complexes with the (S,R) configuration under conditions of thermodynamic control of the nucleophilic addition exceeds 94%. Acid treatment of the reaction mixtures afforded enantiomerically pure (R)-S-hetarylcysteines (ee >98%). 相似文献
4.
T. V. Kochikyan E. V. Harutyunyan V. S. Harutyunyan A. A. Avetisyan 《Chemistry of Heterocyclic Compounds》2006,42(1):109-114
By reaction of 8-substituted 3-bromoacetyl-3,8-dimethyl-2,7-dioxaspiro[4,4]nonane-1,6-diones with thiourea and substituted
thioureas under Hansch reaction conditions, we have obtained the novel heterocycles 3-[2′-amino(arylamino)thiazol-4-yl]-3,8-dimethyl-2,7-dioxaspiro[4,4]nonane-1,6-diones.
By reacting the above-indicated bromoacetyl spirodilactones with 5-aryl-3-mercapto-1,2,4-triazoles, we obtained 8-substituted
3-(aryl-3,8-dimethyl-1′,2′,4′-triazol-3′-yl)thioacetyl-2,7-dioxaspiro[4,4]nonane-1,6-diones.
__________
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 123–129, January, 2006. 相似文献
5.
Harutyunyan A. A. Israyelyan S. G. Panosyan H. A. Hovsepyan T. R. 《Russian Journal of Organic Chemistry》2020,56(7):1211-1216
Russian Journal of Organic Chemistry - One-pot three-component reactions of 2,6-diaminopyrimidin-4-(3H)-one with aromatic aldehydes and 1- or 2-naphthol afforded benzo[7,8]chromeno[2,3-d]pyrimidine... 相似文献
6.
Hovsepyan T. R. Hakobyan M. R. Muradyan R. E. Nersesyan L. E. Aharonyan A. S. Danielyan I. S. Minasyan N. S. Harutyunyan A. A. 《Russian Journal of Organic Chemistry》2020,56(12):2137-2142
Russian Journal of Organic Chemistry - While developing new approaches to the design of biologically active compounds based on 1,2,4-triazole, a number of new hydrazones containing... 相似文献
7.
Kirill Kulish Cosimo Boldrini Dr. Marta Castiñeira Reis Dr. Juana M. Pérez Prof. Dr. Syuzanna R. Harutyunyan 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(68):15843-15846
Two-step dearomative functionalization of naphthols promoted by Lewis acids and copper(I) catalysis was developed. Initially, Lewis acid complexation inverted the electronic properties of the ring and established an equilibrium with the dearomatized counterpart. Subsequent trapping of the dearomatized intermediate with organometallics as well as organophosphines was demonstrated and provided the corresponding dearomatized products. 相似文献
8.
Vardanyan S. O. Avagyan A. S. Aghekyan A. A. Sargsyan A. B. Harutyunyan S. A. Gasparyan H. V. 《Russian Journal of Organic Chemistry》2020,56(3):436-439
Russian Journal of Organic Chemistry - The title compound was synthesized by reaction of 1,4-benzodioxane-2-carbohydrazide with phenyl isothiocyanate, followed by cyclization of the... 相似文献
9.
10.
M Pérez M Fañanás-Mastral V Hornillos A Rudolph PH Bos SR Harutyunyan BL Feringa 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(38):11880-11883
A highly efficient, regio- and enantioselective Cu(I) /phosphoramidite-catalyzed asymmetric allylic alkylation of allyl ethers with organolithium reagents is reported. The use of organolithium reagents is essential for this catalytic C?C bond formation due to their compatibility with different Lewis acids. The versatility of allylic ethers under the copper-catalyzed reaction conditions with organolithium reagents is demonstrated in the shortest synthesis of (S)-Arundic acid. 相似文献