Garegg-Samuelson二醇消除加成

邻二醇与碘、亚膦硝基和咪唑给与碘代亚膦酸酯催化，在锌粉合成下消除给与催化的自由基。

自由基操作

3-O-Benzyl-5,6-dideoxy-1,2-O-isopropylidene-a-D-xylohex-5-enofuranose (3).To a stirred solution of 3-O-benzyl-1,2-O-isopropylidene-a-D-glucofuranose 1 (0.5 g, 1.6 mmol), Im (0.44 g, 6.45 mmol) and chlorodiphenylphosphane (0.78 g, 3.55 mmol) in PhMe (30 mL) was added iodine (0.9 g, 3.55 mmol) portionwise at 80 C. The mixture was stirred for 30 min at reflux temp and Zn powder (1.1 g, 16.1 mmol) was added. After 30 more min of reflux the cooled mixture was washed with 1M NaOH and water. The organic phase on work up and chromatography afforded 3, 0.42 g, 94%;

bp 124–129 C (0.2 Torr).

【Samuelson B, J Org Chem. , 1990, 55, 4273】

相关文献

1 Garegg PJ, Samuelson B Can J Chem 1981 59 339

2 Samuelson B J Org Chem 1990 55 4273

3 Zamojski A Carbohyd Res 1990 205 410

4 Luzzio FA J Org Chem 1994 59 7267

5 Peterson MA Syn Comm 1996 26 2223

6 Tatibouet A J Carbohyd Chem 2000 19 641

7 Tatibouet A Lett Org Chem 2005 2 47

编译自：Organic Syntheses Based On Name Reactions, 3RdEd, A. Hassner, Page 174-175.

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