Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 7 de 7
Filter
Add more filters










Database
Language
Publication year range
1.
Chem Commun (Camb) ; 49(55): 6218-20, 2013 Jul 14.
Article in English | MEDLINE | ID: mdl-23736892

ABSTRACT

A novel Pd(OAc)2-NFSI-TFA system was developed for the highly selective ortho-monofluorination directed by diverse aryl-N-heterocyclic directing groups e.g., quinoxaline, pyrazole, benzo[d]oxazole, and pyrazine derivatives. A Pd(II/IV) catalytic cycle was proposed based on the ESI-MS/MS studies.

2.
Chem Commun (Camb) ; 48(98): 11993-5, 2012 Dec 21.
Article in English | MEDLINE | ID: mdl-23128502

ABSTRACT

An iron-catalyzed benzylic vinylation was developed to transfer the carbon atom in the N,N-dimethyl moiety of N,N-dimethylacetamide (or N,N-dimethylformamide) to 2-methyl azaarenes to generate 2-vinyl azaarenes.


Subject(s)
Iron/chemistry , Phenazines/chemical synthesis , Acetamides/chemistry , Catalysis , Dimethylformamide/chemistry , Hydrogenation , Molecular Structure , Phenazines/chemistry
4.
J Zhejiang Univ Sci B ; 11(2): 102-8, 2010 Feb.
Article in English | MEDLINE | ID: mdl-20104644

ABSTRACT

Both 1,5-benzodiazepine and quinoxaline derivatives are important heterocycles in pharmaceuticals. We describe an efficient and clean method for the synthesis of 1,5-benzodiazepines from o-phenylenediamine and ketones catalyzed by sodium tetrachloroaurate(III) dihydrate under mild conditions. The catalyst was shown to be equally effective for the synthesis of quinoxalines from o-phenylenediamine and alpha-bromo ketones under the similar reaction conditions. This method produced good yields.

5.
J Zhejiang Univ Sci B ; 10(6): 472-8, 2009 Jun.
Article in English | MEDLINE | ID: mdl-19489113

ABSTRACT

In this paper, we presented a novel method for the facile and efficient one-pot synthesis of 2-arylbenzoxazoles, which were directly synthesized from 2-aminophenol and aldehydes catalyzed by hydrogen tetrachloroaurate (HAuCl(4).4H(2)O) under an oxygen atmosphere with anhydrous tetrahydrofuran (THF) as solvent or in solvent-free condition. The results show that this method could bring excellent yields as high as 96%. THF was proven to be the best choice among several solvents screened and the reaction was tolerated with a variety of aromatic aldehydes possessing electron-donating or withdrawing groups. The advantages of the present method lie in catalytic process using economic and environmentally benign dioxygen as oxidant.


Subject(s)
Aldehydes/chemistry , Aminophenols/chemistry , Chlorides/chemistry , Gold Compounds/chemistry , Oxazoles/chemical synthesis , Oxygen/chemistry , Catalysis
6.
J Zhejiang Univ Sci B ; 7(5): 393-6, 2006 May.
Article in English | MEDLINE | ID: mdl-16615170

ABSTRACT

A simple and convenient procedure for stereoselective synthesis of (Z)-allyl selenides has been developed by a one-pot reaction of diselenides with Baylis-Hillman adducts in the presence of samarium metal-trimethylsilyl chloride under mild conditions. Presumably, the diselenides are cleaved by Sm/TMSCl system to form selenide anions, which then undergo S(N)2' substitution of Baylis-Hillman adducts to produce the (Z)-allyl selenides.


Subject(s)
Organoselenium Compounds/chemistry , Selenium Compounds/chemistry , Selenium Compounds/chemical synthesis , Magnetic Resonance Spectroscopy , Molecular Structure , Stereoisomerism
7.
J Zhejiang Univ Sci B ; 7(3): 193-7, 2006 Mar.
Article in English | MEDLINE | ID: mdl-16502505

ABSTRACT

Stereoselective transformation of Baylis-Hillman acetates 1 into corresponding (Z)-allyl iodides 2 has been achieved by treatment of 1 with samarium triiodide in THF. Remarkable rate acceleration of samarium triiodide-mediated iodination of 1 was found when ionic liquid 1-n-butyl-3-methyl-imidazolium tetrafluroborate ([bmim]BF(4)) was used as reaction media in stead of THF. This novel approach proceeds readily at 50 degrees C within a few minutes to afford (Z)-allyl iodides 2 in excellent yields. A mechanism involving stereoselective iodination of the acetates of Baylis-Hillman adducts by samarium triiodide is described, in which a six-membered ring transition state played a key role in the stereoselective formation of 2.


Subject(s)
Acetates/chemistry , Iodides/chemical synthesis , Samarium/chemistry , Ions , Kinetics , Solutions
SELECTION OF CITATIONS
SEARCH DETAIL
...