Results 31 to 40 of about 5,187 (206)

Simple and Expedient Access to Novel Fluorinated Thiazolo- and Oxazolo[3,2-a]pyrimidin-7-one Derivatives and Their Functionalization via Palladium-Catalyzed Reactions

Molecules, 2022
An efficient, versatile, and one-pot method for the preparation of novel fluorinated thiazolo- and oxazolo[3,2-a]pyrimidin-7-ones is described from 2-aminothiazoles or 2-amino-oxazoles and fluorinated alkynoates.
Wafa Blancou, Badr Jismy, Soufiane Touil, Hassan Allouchi, Mohamed Abarbri   +4 more
doaj   +1 more source

A new synthesis of oxazoles

, 1980
Oxazoles are prepared from the ketoximes in a single pot ...
Bhatt, MV, Reddy, Gaddam Subba
core   +2 more sources

1,4- Addition of diazomethane to a heterodiene: a direct preparation of the oxazolic ring

Anais da Academia Brasileira de Ciências, 2007
The reaction of naphthoquinone-oximes (3) and (4) with diazomethane yields directly, in one step, the oxazoles (5) and (6), respectively.A reação das naphthoquinona-oximas (3) e (4) com diazometano fornece diretamente, em uma etapa, os oxazóis (5) e (6),
Flávio da S. Emery, Raphael S.F. Silva, Kelly C.G. de Moura, Maria C.F.R. Pinto, Mauro B. Amorim, Valéria R.S. Malta, Regina H.A. Santos, Kátia M. Honório, Albérico B.F. da Silva, Antonio V. Pinto   +9 more
doaj   +1 more source

2-(3-Bromophenyl)imidazo[2,1-b]oxazole

Molbank, 2023
The microwave-assisted reaction of 2-nitroimidazole with 3-bromophenacyl bromide in the presence of potassium carbonate as a base and dimethylformamide as a solvent afforded 2-(3-bromophenyl)imidazo[2,1-b]oxazole.
Ángel Cores, Mercedes Villacampa, J. Carlos Menéndez   +2 more
doaj   +1 more source

Investigation on the reactivity of α-azidochalcones with carboxylic acids: Formation of α-amido-1,3-diketones and highly substituted 2-(trifluoromethyl)oxazoles

Beilstein Journal of Organic Chemistry, 2015
The reaction of α-azidochalcones with carboxylic acids has been investigated resulting in the formation of α-amido-1,3-diketones under microwave irradiation via in situ formation of 2H-azirine intermediates.
Kandasamy Rajaguru, Arumugam Mariappan, Rajendran Suresh, Periasamy Manivannan, Shanmugam Muthusubramanian   +4 more
doaj   +1 more source

The LANCA three-component reaction to highly substituted β-ketoenamides – versatile intermediates for the synthesis of functionalized pyridine, pyrimidine, oxazole and quinoxaline derivatives

Beilstein Journal of Organic Chemistry, 2019
The LANCA three-component reaction of lithiated alkoxyallenes LA, nitriles N and carboxylic acids CA leads to β-ketoenamides KE in good to excellent yields.
Tilman Lechel, Roopender Kumar, Mrinal K. Bera, Reinhold Zimmer, Hans-Ulrich Reissig   +4 more
doaj   +1 more source

Base-Catalyzed Cyclization of N-Sulfonyl Propargylamides to Sulfonylmethyl-Substituted Oxazoles via Sulfonyl Migration

, 2013
The reaction of N-sulfonyl propargylamides in the presence of a base catalyst selectively affords 5-sulfonylmethyl oxazoles via 1,4-sulfonyl migration. Allenes have been established as the key intermediates.
Wan, Boshun, 李兴伟, Yu, Xinzhang, Li, Xingwei, 万伯顺, Xin, Xiaoyi   +5 more
core   +1 more source

Recent Advances on O-Ethoxycarbonyl and O-Acyl Protected Cyanohydrins

Molecules, 2021
Ethoxycarbonyl cyanohydrins and O-acyl cyanohydrins are examples of O-protected cyanohydrins in which the protecting group presents an electrophilic center, contributing to additional reaction pathways.
Héctor Manuel Torres Domínguez, Luis Mauricio Hernández Villaverde, Ronan Le Lagadec   +2 more
doaj   +1 more source

Synthesis of 2,4,5-trisubstituted oxazoles [PDF]

, 2005
2,4,5-Trisubstituted oxazoles were synthesized in good yields starting from alpha-methylene ketones by nitrosation, condensation with aldehydes and reduction with zinc in acetic acid at 40 degrees C.
Zhang, GL, Chinese Acad Tradit Chinese Med, Chengdu Inst Biol, Chengdu 610041, Peoples R China., Cai, XH, Yang, HJ, Zhang, GL   +3 more
core  

A Direct Synthesis of Oxazoles from Aldehydes

, 2016
An expedient method for the direct conversion of aldehydes to 2,4-disubstituted oxazoles is presented. The method relies on the oxidation of an oxazolidine formed from the condensation of serine with an aldehyde and proceeds through a 2,5-dihydrooxazole ...
Thomas H. Graham (2141350)
core   +2 more sources