Synthesis, structure and electronic properties of N-dialkylamino- and N-alkoxy-1,2,4-triazol-3-ylidene ligands
摘要:
4-Amino- and 4-alkoxy-1,2,4-triazoles 4a-d and 6 were readily obtained from the reaction of N,N-dimethyiformamidazin dihydrochloride 3 with hydrazines 2 and hydroxylamine 5. Alkylation of compounds 4a-d and 6 by MeOTf or MeI afforded azolium salts 9-11, which in turn were transformed into Rh(l) carbene complexes 13-15, Ag carbenes 16, and cationic Rh(l) bis-carbenes 17. Additionally.. complexes 13 and 15 were transformed into dicarbonyl derivatives 18 and 19, and the carbonyl stretching frequencies of these compounds were used to evaluate the effect of the amino and alkoxy groups in the sigma-donor ability of these 1,2,4-triazol-3-ylidenes. (c) 2005 Elsevier B.V. All rights reserved.
Ultrasound-assisted synthesis of 2,5-dimethyl-N-substituted pyrroles catalyzed by uranyl nitrate hexahydrate
作者:V.S.V. Satyanarayana、A. Sivakumar
DOI:10.1016/j.ultsonch.2011.02.007
日期:2011.9
An efficient synthesis of different novel 2,5-dimethyl-N-substituted pyrrole derivatives by the Paal-Knorr condensation has been accomplished using uranylnitratehexahydrate as catalyst under soft conditions and ultrasonic irradiation. The synthesized compounds were confirmed through spectral characterization using IR, (1)H NMR, (13)C NMR and mass spectra.