inexpensive, nontoxic manganese catalyst enabled unprecedented redox‐neutral carbonylative annulations under ambient pressure. The manganese catalyst outperformed all other typically used base and precious‐metal catalysts. The outstanding versatility of the manganese catalysis manifold was reflected by ample substrate scope, setting the stage for effective late‐stage manipulations under racemization‐free
cross-coupling reaction has been developed under mild electrolytic conditions. In this atom- and step-economical one-pot process, valuable 1,2,4-triazolo[4,3-a]pyridines and related heterocyclic compounds could be synthesized efficiently from commercially available aliphatic or (hetero)aromatic aldehydes and 2-hydrazinopyridines. Various functional groups are compatible with this metal- and oxidant-free
在温和的电解条件下已开发出无试剂的分子内脱氢C–N交叉偶联反应。在这种原子经济和一步经济的一锅法中,有价值的1,2,4-三唑并[4,3- a ]吡啶和相关的杂环化合物可以从可商购的脂族或(杂)芳族醛和2-肼基吡啶。各种官能团都与这种无金属和无氧化剂的方案兼容,可以轻松地以克为单位进行操作。这种新方法被应用于最畅销药物Xanax的合成和后期功能化,以在生物学相关的先导分子中产生化学多样性。
Synthesis and Antimicrobial Activities of Novel 2-[substituted-1<i>H</i>-pyrazol-4-yl] Benzothiazoles, Benzoxazoles, and Benzimidazoles
作者:Vikas S. Padalkar、Bhushan N. Borse、Vinod D. Gupta、Kiran R. Phatangare、Vikas S. Patil、Nagaian Sekar
DOI:10.1002/jhet.1506
日期:2016.9
find a new class of antimicrobialagents, a series of novelsubstituted benzimidazole, benzoxazole, and benzothiazole derivatives6 containing pyrazole moiety have been synthesized by reaction of 3‐aryl‐4‐formyl pyrazole 4 with substituted phenylenediamine or o‐aminophenol or o‐aminothiophenol 5. Reaction of phenyl hydrazine or 2‐hydrazinopyridine 1 with substituted acetophenones 2 gave the corresponding
C–O Coupling of Hydrazones with Diacetyliminoxyl Radical Leading to Azo Oxime Ethers—Novel Antifungal Agents
作者:Alexander S. Budnikov、Igor B. Krylov、Mikhail I. Shevchenko、Oleg O. Segida、Andrey V. Lastovko、Anna L. Alekseenko、Alexey I. Ilovaisky、Gennady I. Nikishin、Alexander O. Terent’ev
DOI:10.3390/molecules28237863
日期:——
Selective oxidative C-O coupling of hydrazones with diacetyliminoxyl is demonstrated, in which diacetyliminoxyl plays a dual role. It is an oxidant (hydrogen atom acceptor) and an O-partner for the oxidative coupling. The reaction is completed within 15-30 min at room temperature, is compatible with a broad scope of hydrazones, provides high yields in most cases, and requires no additives, which makes
[Hydroxy(tosyloxy)iodo]benzene mediated the oxidative cleavage of pyridyl hydrazones to regenerate aryl ketones efficiently. Reaction occurred by simply stirring the hydrazone with hypervalent iodinereagent in dichloromethane at room temperature, where aryl ketones are produced up to 90% yield.