Results 51 to 60 of about 19,339 (247)

An Example of Polynomial Expansion: The Reaction of 3(5)-Methyl-1H-Pyrazole with Chloroform and Characterization of the Four Isomers

Molecules, 2019
The reaction in phase-transfer catalyzed conditions of 3(5)-methyl-1H-pyrazole with chloroform affords four isomers 333, 335, 355 and 555 in proportions corresponding to the polynomial expansion (a + b)3, with a = 0.6 and b = 0.4, a and b being 3-methyl ...
Vera L. M. Silva, Artur M. S. Silva, Rosa M. Claramunt, Dionisia Sanz, Lourdes Infantes, Ángela Martínez-López, Felipe Reviriego, Ibon Alkorta, José Elguero   +8 more
doaj   +1 more source

Katalytischer Schwefelatomtransfer vermittelt durch einen Bis(disulfido)‐Titankomplex

Angewandte Chemie, EarlyView.
Mehrelektronentransformationen mit Titan sind aufgrund der limitierten Zugänglichkeit niedervalenter Vorstufen bislang nur unzureichend untersucht. Die Vier‐Elektronen‐Aktivierung von elementarem Schwefel durch einen Ti(IV)‐Komplex führt zu einem seltenen Bis(disulfido)‐Titankomplex, der die effiziente katalytische Synthese von Isothiocyanaten aus ...
Sebastian Samir Cremer, Peter Coburger, Corinna Czernetzki, Gabriele Hierlmeier   +3 more
wiley   +1 more source

Temperature-Controlled Divergent Synthesis of Pyrazoles and 1-Tosyl-1H-pyrazoles under Transition-Metal-Catalyst- and Oxidant-Free Conditions

Molecules
Herein, a general and practical temperature-controlled approach for the divergent synthesis of pyrazoles and 1-tosyl-1H-pyrazoles via electrophilic cyclization in the absence of transition-metal catalysts and oxidants was developed.
Kai Wang, Wenjing Xu, Chengcai Xia, Xianting Cao   +3 more
doaj   +1 more source

Synthesis of Pyrazoles from 1,3-Diols via Hydrogen Transfer Catalysis

, 2016
1,3-Diols engage in ruthenium-catalyzed hydrogen transfer in the presence of alkyl hydrazines to provide 1,4-disubstituted pyrazoles.
Andrew C. Flick (1633114), Alexandria P. Taylor (1633120), Robert E. Kyne (1633123), Daniel C. Schmitt (1633117)   +3 more
core   +1 more source

Synthesis of 4-functionalized pyrazoles via oxidative thio- or selenocyanation mediated by PhICl2 and NH4SCN/KSeCN

Beilstein Journal of Organic Chemistry
A series of 4-thio/seleno-cyanated pyrazoles was conveniently synthesized from 4-unsubstituted pyrazoles using NH4SCN/KSeCN as thio/selenocyanogen sources and PhICl2 as the hypervalent iodine oxidant.
Jialiang Wu, Haofeng Shi, Xuemin Li, Jiaxin He, Chen Zhang, Fengxia Sun, Yunfei Du   +6 more
doaj   +1 more source

Synthesis of Novel Pyrazole Derivatives and Their Tumor Cell Growth Inhibitory Activity

Molecules, 2019
To find novel antitumor agents, a series of 1H-benzofuro[3,2-c]pyrazole derivatives 4a-e were designed and synthesized. The treatment of 6-methoxybenzofuran-3(2H)-one 3 with LiHMDS in anhydrous tetrahydrofuran (THF) followed by reaction with 3-substitued
Ying-Jie Cui, Long-Qian Tang, Cheng-Mei Zhang, Zhao-Peng Liu   +3 more
doaj   +1 more source

Pyrazoles as Key Scaffolds for the Development of Fluorine-18-Labeled Radiotracers for Positron Emission Tomography (PET)

Molecules, 2020
The need for increasingly personalized medicine solutions (precision medicine) and quality medical treatments, has led to a growing demand and research for image-guided therapeutic solutions.
Pedro M. O. Gomes, Artur M. S. Silva, Vera L. M. Silva   +2 more
doaj   +1 more source

Synthesis of pyrazole and pyrazole amidocobaloximes

, 2004
Department of Chemistry, Osmania University, Hyderabad-500 007, India E-mail : ssnsirasani @yahoo.com Manuscript received 23 September 2002, revised 23 April 2003. accepted 11 July 2003 A series of cyano (ligand) cobaloximes have been prepared where, the ligand is pyrazole (Pz), 1-(acetamido)pyrazole (Apz), 1-(N-methylacetamido)pyrazole (MAPz), 1 ...
A. Rajeshwar Rao, G. Gopinath, J. V. Madhuri, S. Satyanarayana   +3 more
openaire   +1 more source

‐Substituted Pyrazoles

, 2020
An efficient one-pot, two step method for fusing two biologically active motifs, CF3-substituted pyrazoles and isochromenes, was developed. Selective O-benzylation of CF3-substituted pyrazolones and subsequent Pd-catalyzed direct C–H arylation generate a
Života Selaković, Selaković, Života, Igor M. Opsenica, Wipf, Peter, Filip Živković, Opsenica, Igor, Andrea M. Nikolić, Peter Wipf, Živković, Filip, Nikolić, Andrea   +9 more
core   +1 more source

Carbamidine-substituted Pyrazoles [PDF]

Nature, 1951
THE ease with which 1-substituted pyrazoles may be converted into the free imino compounds varies with the nature of the 1-substituent and the reacting substance. Thus, 1,3,5-trimethyl pyrazole may be nitrated1 and 1-phenyl pyrazole reduced to the pyrazoline2 without loss of the N-methyl or N-phenyl groups respectively.
F L, SCOTT, C M B, MURPHY, J, REILLY
openaire   +2 more sources