Ruthenium−p-cymene complexes with acylthiourea, and its heterogenized form on graphene oxide act as catalysts for the synthesis of quinoxaline derivatives
Synthesis of a series of half-sandwich Ru(II) complexes (1-5) containing acylthiourea ligand is reported herein. All the Ru(II) complexes were well characterized by analytical and spectroscopic (UV-Vis, FT-IR, NMR and mass spectrometry) methods. Molecular structures of two (2 and 3) of the complexes were confirmed by single crystal X-ray diffraction, and the complexes adopted pseudo-octahedral geometry around
Direct Selective Oxidative Cross-Coupling of Simple Alkanes with Heteroarenes
作者:Andrey P. Antonchick、Lars Burgmann
DOI:10.1002/anie.201209584
日期:2013.3.11
A dream reaction: An efficient and practical method for the oxidative cross‐coupling of heteroaromatic compounds and simplealkanes has been developed. The desired products are smoothly and regioselectively formed under mild reaction conditions at ambient temperature in a hypervalent‐iodine‐mediated transformation. The method allows for preferential transformation of stronger CH bonds in the presence
2,3-Diphenylated quinoxaline, pyrido[2,3-b]pyrazine and 8-bromopyrido[3,4-b]pyrazine were halogenated in deprotometalation-trapping reactions using mixed 2,2,6,6-tetramethyl piperidino-based lithium-zinc combinations in tetrahydrofuran. The 2,3-diphenylated 5-iodo- quinoxaline, 8-iodopyrido[2,3-b]pyrazine and 8-bromo-7-iodopyrido[3,4-b]pyrazine thus obtained were subjected to palladium-catalyzed couplings
A variety of 2,3-disubstituted quinoxalines are readily prepared in high yields under extremely mild conditions by cyclocondensation of arene-1,2-diamines with 1,2-dicarbonyls using a catalytic amount of bismuth(III) triflate. The reactions of 2,3-diaminopyridine with 1,2-dicarbonyls produce pyrido[2,3-b]pyrazine derivatives under similar conditions.
A Fe(III)/NaBH<sub>4</sub>-Promoted Free-Radical Hydroheteroarylation of Alkenes
作者:Bingyu Liang、Qinglong Wang、Zhong-Quan Liu
DOI:10.1021/acs.orglett.7b03313
日期:2017.12.15
A free-radical-mediated intermolecular hydroheteroarylation of simple alkenes was developed. Through simply mixing heteroarenes, alkenes, Fe(III), and NaBH4 at 0 °C together, a wide range of alkylated heteroarenes could be afforded in moderate to excellent yields within 1 h.