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