- Metal- And Oxidant-Free Electrochemical Oxidative Desulfurization C-O Coupling of Thiourea-Type Compounds with Alcohols
-
An efficient desulfurization C-O coupling reaction of 3,4-dihydropyrimidine-2(1 H)-thiones (including thioureas) with alcohols was developed under electrochemical oxidation conditions. Herein, transition--metal catalysts and additives are not required and
- Cao, Bao-Qian,Quan, Zheng-Jun,Ren, Ming-Zhe,Wang, Xi-Cun,Zhu, Zheng-He
-
p. 1634 - 1642
(2020/05/25)
-
- Thieme chemistry journal awardees - Where are they now? Stereoselective synthesis of z-configured α,β-unsaturated macrocyclic lactones and diolides by intramolecular julia-kocienski olefination
-
ω-Sulfonyl aldehydes derived from the esterification of (benzothiazol-2-ylsulfonyl)acetic acid with either ω-alkenols or α, ω-diols, followed by ozonolysis or Dess-Martin oxidation as appropriate, underwent intramolecular Julia-Kocienski olefination when treated with DBU. Macrocyclic α,β-unsaturated lactones of between 12- and 19-membered ring sizes were formed successfully using this tactic (24-44% yield, Z/E ≥ 3.5:1); however, diolides were selectively produced from precursors intended to target seven- to nine-membered-ring lactones (13-70% yield, ZZ/ZE ≥ 2:1). Georg Thieme Verlag Stuttgart New York.
- Giesbrecht, Heath E.,Knight, Brian J.,Tanguileg, Nicole R.,Emerson, Christopher R.,Blakemore, Paul R.
-
scheme or table
p. 374 - 378
(2010/04/06)
-
- Kinetic and Mechanistic Studies of the Reactions between 2-Nitrothiazole, 2-Nitrobenzothiazole and some Nucleophiles
-
Kinetic data for the reactions between some 2-nitrothiazoles and nucleophiles (alkoxide and piperidine) are reported.The kinetic behaviour of the nitro group parallels that of the more usual leaving groups and a two-step mechanism involving nucleophilic aromatic substitution may be suggested to be in operation.A change of counter ion (Li(1+), Na(1+), K(1+) of the anionic nucleophile indicates that the presence of the ion pairs partially favours reactivity, probably by interaction with the nitro group.The autocatalytic behaviour of the reactions between 2-nitrothiazole and piperidine is explained by the presence of an interaction between the substrate and the nucleophile in an equilibrium preceding the substitution process.Comparison of the nucleofugicity of nitro and chloro groups (as leaving groups) indicates that the presence of hydrogen bonds between the leaving group and the solvent (or the nucleophile) produces considerable variations in the observed reactivities.
- Forlani, Luciano
-
p. 1699 - 1702
(2007/10/02)
-
- Method for preparing 4-substituted-N-methylbenzothiazolone derivatives
-
A process for producing N-alkylbenzothiazolone derivatives of the formula (I), STR1 wherein R1 is a hydrogen, chlorine, bromine, fluorine atom or a methyl group, and R2 is an alkyl group having 1 to 5 carbon atoms, from 2-halogenobenzothiazole derivatives of the formula (II), STR2 wherein R1 is as defined above and X is a chlorine, bromine or fluorine atom, which is a starting material, through the intermediate of 2-alkoxybenzothiazole derivatives of the formula (III), STR3 wherein R1 and R2 are as defined above, or benzothiazolone derivatives of the formula (IV), STR4 wherein R1 is as defined above.
- -
-
-