An Alternative Approach Towards the Syntheses of Thioethers and Thioesters Using CsF-Celite In Acetonitrile (original) (raw)
Related papers
CsF-Celite, an Efficient Solid State Reagent for the Syntheses of Thioesters and Thioethers
Monatshefte für Chemie - Chemical Monthly, 2005
Coupling reactions of a number of aliphatic, aromatic, and heterocyclic compounds bearing an acidic hydrogen atom attached to sulfur, with alkyl, acyl, benzyl, or benzoyl halides in acetonitrile with cesium fluoride-Celite are described. This procedure is convenient, efficient, and practical for the preparation of thioethers and thioesters.
Advanced Synthesis & Catalysis, 2010
In this article, we have developed a new protocol for the thioarylation of structurally diverse alkyl bromides such as benzyl, cinnamyl, n-octyl, cyclohexyl, cyclopentyl, and tert-butyl bromides with aryl iodides, bromides and an activated chloride using thiourea catalyzed by copper(I) iodide in wet polyethylene glycol (PEG 200) as an eco-friendly medium in the presence of potassium carbonate at 80 and 100 8C under an inert atmosphere. The process is free from foul-smelling thiols which makes this method more practical for the thioetherification of aryl halides. Another important feature of this method is the variety of alkyl bromides which are commercially available for the in situ generation of thiolate ions with respect to the existing protocols in which the less commercially available thiols are directly used for the preparation of arylthio ethers.
Synthesis of Mono- and N,N - Disubstituted Thioureas and N -Acylthioureas
Synthesis, 2004
1-Benzotriazole-1-carbothioamide (2), prepared from 1cyanobenzotriazole (1) and hydrogen sulfide, reacts with amines to give thioureas 3a-e. Reactions of (benzotriazol-1-yl)carboximidamides 4a-d,f-j and acyl-5a-f,i-k or arylaminocarbonyl-5g,h (benzotriazol-1-yl)carboximidamides with hydrogen sulfide give the corresponding thioureas 3a-d,f-j, and N-acylthioureas 6a-f,i-k or N-carbamoylthioureas 6g,h, respectively.
International Journal of Scientific Research in Science and Technology, 2020
Thiazole represents important class of heterocyclic compounds. Thiazole and its derivatives have been reported to possess antitubercular, antibacterial, anti-inflammatory, anticancer, antifungal activity. Several methods of synthesis of thiazole derivatives have been reported, but most widely used synthetic approach to obtained thiazole derivatives is Hantzsch process. It involved synthesis of thiazole derivative from ?-halo-carbonyl compounds and thiourea or thiourea derivatives. This review mainly focuses on the research work reported in the scientific literature on the different procedures of synthesis of 2-amino thiazole and their derivatives.
Tetrahedron Letters, 2007
A general, clean and easy method for the conjugated addition of thiols to citral promoted by KF/Al 2 O 3 under solventfree conditions at room temperature or under MW irradiation is described. It was found that the same protocol is applicable to the direct reaction of thiophenol with essential oil of lemon grass (Cymbopogon citratus) to afford directly 3-thiophenylcitronellal, a potential bactericide agent. The method was extended to others electron-poor alkenes with excellent results. The catalytic system can be reused up to three times without previous treatment with comparable activity.
Heteroatom Chemistry, 2006
The behavior of ethyl 2-phenylthiocarbamoyl acetate 1 toward a variety of several ␣-halocarbonyl compounds was investigated. Thus, reaction of 1 with ␣-bromoketones, hydrazonoyl bromides, and 2-chloro-N-arylacetamides afforded the corresponding dihydrothiazole, 1,3,4-thiadiazole, and thiophene derivatives, respectively. The synthesis of thiazolidin-4one 11, thiazolidin-5-one 12, and some azo derivatives of thiazolidin-5-one were described. 5-Arylazothiazoles 17 and 19 were synthesized by condensation of hydrazonoyl bromides 3 with different thiourea derivatives.
Mechanistic Study on the Formation of Compounds from Thioureas
InTech eBooks, 2018
Formation of 2-(N-arylamino)benzothiazole takes place, when N,N 0-diphenylthioureas are treated with polymer-supported tribromide or with iodine-alumina as catalyst under solvent free conditions. However, when N-substituted-N 0-benzoylthioureas are treated with polymer-supported tribromide or with iodine-alumina as catalyst either under various conditions or under solvent free conditions, decomposition takes place to give the respective benzamides and thiobenzamides. Mechanistic study of the formation of these compounds is studied using DFT calculations. It is found that electron donating group at the para-position of the aryl group of benzoylthiourea favors the formation of benzamide whereas the presence of electron withdrawing group at para-position of the aryl group of benzoylthiourea, formation of thiobenzamide takes place. When the catalyst is changed to diacetoxyiodobenzene (DIB) under similar reaction conditions, benzoxazole amides are formed; expected benzothiazoles or the decomposition products are not obtained. Mechanistic study of the reaction using DFT calculation again shows that the reaction followed through carbodiimide intermediate undergoes the formation of CO bond in benzoxazole moiety, instead of the expected C-S bond formation of benzothiazole moiety via a sequential acylation and deacylation process.
Synthesis and oxidation of some azole-containing thioethers
Beilstein Journal of Organic Chemistry, 2011
Pyrazole and benzotriazole-containing thioethers, namely 1,5-bis(3,5-dimethylpyrazol-1-yl)-3-thiapentane, 1,8-bis(3,5dimethylpyrazol-1-yl)-3,6-dithiaoctane and 1,3-bis(1,2,3-benzotriazol-1-yl)-2-thiapropane were prepared and fully characterized.