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化学大会:2019 - Gold-catalyzed 3-trimethylsilyl代替唑的合成丙炔醇类和酰胺- Nobuyoshi盛田昭夫

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恶唑是一种结构性主题大量的天然产物和生物活性的化合物。在许多程序代替唑的合成报道,cycloisomerization丙炔酰胺取代唑吸引了太多的关注。另一方面,直接从丙炔醇代替唑的合成和通过丙炔酰胺酰胺中间体仍然是一个挑战性的任务,尽管丙炔替换和后续cycloisomerozation可能有效地在相同的反应条件下进行。在此,我们报告的合成取代由gold-catalyzed唑丙炔替换紧随其后cycloisomerizationβ-cation-stabilizing效果提升的硅原子的3-trimethylsilyl丙炔醇。在化学合成可能的策略来提高反应的效率,连续反应物受到化学反应只在一个反应堆。这通常是所需的化学家因为避免漫长的分离过程和净化的中间化合物可以节省时间和资源,同时增加化学收率。合成的一个例子是,总托品酮的合成或Gassman吲哚合成。连续锅合成通常不会产生与多个stereocentres甚至复杂的目标,像奥司他韦,可以显著缩短整体所需的步骤,具有重要的商业意义。顺序与合成试剂添加到反应堆一次,没有检查另外称为伸缩式合成。在这样一个过程3-N-tosylaminophenol我和二丙烯醛的反应提供一个羟基取代喹啉3到4顺序步骤没有检查中间产品的恶唑是一个巨大的母体化合物类的杂环芳香族有机化合物。 These are azoles with an oxygen and a nitrogen separated by one carbon. Oxazoles are aromatic compounds but less so than the thiazoles. Oxazole may be a weak base; its conjugate acid features a pKa of 0.8, compared to 7 for imidazole. The Robinson–Gabriel synthesis by dehydration of 2-acylaminoketones. The Fischer oxazole synthesis from cyanohydrins and aldehydes. The Bredereck reaction with α-haloketones and formamide . The Van Leusen reaction with aldehydes and TosMIC In chemistry , an amide, also referred to as an organic amide or a carboxamide, may be a compound with the overall formula RC(=O)NR′R″, where R, R′, and R″ represent organic groups or hydrogen atoms. The amide group is named a peptide linkage when it's a part of the most chain of a protein, and isopeptide bond when it occurs during a side chain, like within the amino acids asparagine and glutamine. It are often viewed as a derivative of a acid RC(=O)OH with the hydroxyl –OH replaced by an amine group –NR′R″; or, equivalently, an acyl (alkanoyl) group RC(=O)– joined to an amine group. Common samples of amides are acetamide H3C–CONH2, benzamide C6H5–CONH2, and dimethylformamide HCON(–CH3)2. Amides are qualified as primary, secondary, and tertiary consistent with whether the amine subgroup has the shape –NH2, –NHR, or –NRR′, where R and R′ are groups aside from hydrogen.[not verified in body] The core –C(=O)N= of amides is named the amide group (specifically, carboxamide group). Amides are pervasive in nature and technology. Proteins and important plastics like Nylons, Aramid, Twaron, and Kevlar are polymers whose units are connected by amide groups (polyamides); these linkages are easily formed, confer structural rigidity, and resist hydrolysis

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