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次氯酸，甲硫基乙酸酯和碱依次加入到苯胺或取代苯胺中一锅法得到3-甲硫基羟吲哚的反应被称为Gassman羟吲哚合成反应。甲硫基可以氢化去掉或者用Raney镍还原。

反应机理

次氯酸化合物先氧化苯胺得到N-氯代苯胺，β-羧基硫化物亲核进攻N-氯代苯胺，生成锍鎓离子，碱拔羧基α位氢，接着进行两次,3]-单电子重排（Sommelet-Hauser）关环，得到产物。

反应实例

Oxindole (5).  To a stirred, cooled (65 C) solution of aniline 1 (4.099 m, 44 mmol) in DCM (150 mL) was added dropwise t-butyl hypochlorite (4.77 g, 44 mmol) in DCM (20 mL). After 10 min, ethyl methylthioacetate 2 (5.89 g, 44 mmol) in DCM (20 mL) was added (exothermic) and stirring was continued for 1 h. Et3N (4.44 g, 44 mmol) in DCM (20 mL) was added. The mixture was allowed to warm to r.t., water (50 mL) was added and the organic layer was evaporated. The residue was redissolved in Et2O (150 mL) and was stirred with 2N HCl (20 mL) for 24 h. Filtration afforded 6.61 g of 4 (84%). A solution of 4 (2 g, 11 mmol) in anhyd EtOH (50 mL) was stirred and refluxed with W-2 Raney nickel (12 g) for 2 h. The supernatant and the washings were evaporated and the residue was dissolved in DCM (20 mL). Drying and evaporation gave 1.13 g of 5 (76%), mp 116–117 C.

【Gassman PG, J Am Chem Soc, 1974, 96, 5506】

相关文献

1 Gassman PG J Am Chem Soc 1973 95 2718

2 Gassman PG J Am Chem Soc 1974 96 5506

3 Johnson PD J Org Chem 1990 55 1374

4 Wright SM Tet Lett 1996 37 4631

5 Teng D Molecules 2006 11 700

6 Yu Y J Combin Chem 2007 9 566

编译自：Organic Syntheses Based On , 3RdEd, A. Hassner, Page 177.

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