α-羟基酮先和酰氯反应生成α-羟酰基酮,接着与乙酸铵或氨脱水关环生成恶唑的反应。除了中间体3,氰醇酯也可以进行此反应。 反应机理 反应操作 2-Methyl-4,5-diphenyloxazole (4). A mixture acetylbenzoin 3 (6.35 g), ammonium acetate (10 g), and HOAc (25 mL) was refluxed for 1 h. The reaction mixture was treated with water (100 mL) and extracted with PhH (3 25 mL). Workup and vacuum distillation afforded 4.8 g (82%) of 4 as a viscous oil, bp 210–213 C/18 mm. 【Davidson D, J Org Chem, 1937, 2, 328】 相关文献 1 Davidson D J Org Chem 1937 2 328 2 Willey RH Chem Rev 1945 37 401 3 Theiling S Chem Ber 1953 86 96 4 Cornforth JW J Chem Soc 1953 93 5 Budevich M Chem Ber 1954 87 700 6 Rangnekar DW Dyes Pigments 1989 10 69 7 Whitney SE J Org Chem 1991 56 3058 8 Beletskii EV Russ J Org Chem 2009 45 1229 相关反应 Bredereck噁唑合成法(Bredereck Oxazole Synthesis) 康福斯重排反应(Cornforth Rearrangement) 编译自:Organic Syntheses Based On Name Reactions, 3RdEd, A. Hassner, Page 116. |
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