A sonochemical method for the synthesis of 2-aminobenzimidazoles and 2-aminobenzoxazoles, as well as chiral aminooxazolines and a chiral substituted quinazolin-5-one is reported. Using the Ph3P–I2 system in the presence of triethylamine as a desulfurization agent, monothioureas prepared in situ from the reaction of bis-nucleophiles with isothiocyanates underwent rapid cyclization to afford a variety
A Cu<sub>2</sub>O/TBAB-promoted approach to synthesize heteroaromatic 2-amines <i>via</i> one-pot cyclization of aryl isothiocyanates with <i>ortho</i>-substituted amines in water
An efficient approach to synthesize heteroaromatic 2-amines from one-pot desulfurization/dehydrogenative cyclization of aryl isothiocyanates with ortho-substituted amines in water was developed. This approach tolerated a wide range of functional groups on the aromatic ring, providing a practical and environment-friendly process to synthesize heteroaromatic 2-amines in moderate to excellent yields.
开发了一种在水中用邻位取代胺一锅法脱硫/脱氢环化芳基异硫氰酸酯合成杂芳族 2-胺的有效方法。这种方法在芳环上具有多种官能团,提供了一种实用且环境友好的方法,可以以中等至优异的产率合成杂芳族 2-胺。提出了一种似是而非的机制,并借助 ESI 质谱法提出了 TBAB 和 Cu 2 O 在本策略中的作用。
Electrochemical NaI/NaCl-mediated one-pot synthesis of 2-aminobenzoxazoles in aqueous media<i>via</i>tandem addition–cyclization
An electrochemical synthesis of 2-aminobenzoxazoles from 2-aminophenols and isothiocyanates was successfully developed in a one-pot fashion. Using inexpensive and widely available NaI and NaCl co-operatively in catalytic amounts, our electrosynthesis approach provided various 2-aminobenzoxazole products in moderate to high yields in an open-flask type undivided cell without using any external supporting
以一锅法成功开发了由 2-氨基苯酚和异硫氰酸酯电化学合成 2-氨基苯并恶唑。我们的电合成方法以催化量合作使用廉价且广泛可用的 NaI 和 NaCl,在不使用任何外部支持电解质和碱的情况下,在开放式烧瓶型未分隔电池中以中等至高产率提供各种 2-氨基苯并恶唑产品。该协议可用于以中等产率从相应的 2-苯硫酚合成 2-氨基苯并噻唑。该协议有很多好处。它不含金属且具有高度可扩展性,并在温和条件下使用廉价的介质和乙醇/水作为环保溶剂。
One-Pot Synthesis of Five and Six Membered N, O, S-Heterocycles Using a Ditribromide Reagent
作者:Ramesh Yella、Bhisma K. Patel
DOI:10.1021/cc100124q
日期:2010.9.13
In a one-pot procedure, bromine less brominating reagent 1,1′-(ethane-1,2-diyl)dipyridinium bistribromide (EDPBT) has been utilized as an efficient desulfurizing agent for the construction of a library of heterocycles containing N, O, and S starting from aryl/alkyl isothiocyanates. In this approach, aryl/alkyl isothiocyanate reacts with o-phenylenediamine (o-PD), o-aminophenol, and o-aminothiophenol
Fe/S-Catalyzed Redox Condensation of <i>o</i>-Nitrophenols with Isothiocyanates to 2-Aminobenzoxazoles
作者:Le Anh Nguyen、Supasorn Phaenok、Duc Long Le、Thi Thu Tram Nguyen、Quoc Anh Ngo、Thanh Binh Nguyen
DOI:10.1021/acs.orglett.3c01897
日期:2023.7.14
and related sulfur containingcompounds should be treated in a safe way to lower their adverse health and environmental effects, especially in large scale syntheses. As a proof of concept, we report herein an example of in situ recycling of sulfur byproduct to reductant in the synthesis of bioactive 2-aminobenzoxazoles 3. Using an Fe/S catalytic system, this heterocyclic scaffold could be obtained from