Cristol-Firth脫羰鹵代反應(yīng)

在加熱或光照條件，羧酸經(jīng)過(guò)氧化汞和鹵素（主要是溴或碘）處理，羧基取代為相應(yīng)的鹵素的反應(yīng)。此反應(yīng)與類似也自由基機(jī)理。此反應(yīng)與相比，可以用羧酸和氧化汞一鍋法進(jìn)行鹵代，而不用于先轉(zhuǎn)化為相應(yīng)的羧酸銀鹽。

反應(yīng)機(jī)理

【Strategic Applications of Named Reactions in OrganicSynthesis, László Kürti and Barbara Czakó, Hunsdiecker reaction，page 218】

反應(yīng)實(shí)例

Chlorobromobenzene (2). A solution of p-chlorobenzoic acid 1 (1.56 g, 10 mmol) in CCl4 (50 mL) and red HgO (15 mmol) was refluxed and irradiated (100 Wbulb). Bromine (15 mmol) was added via a syringe. After 3 h the mixture was cooled to 20 C and washed (aq NaHCO3, 30 mL). Usual workup afforded 1.5 g of 2 (80%).

【Meyers AI, J Org Chem, 1979, 44, 3405】

相關(guān)文獻(xiàn)

1 Cristol S, Firth W J Org Chem 1961 26 280

2 Cason J J Org Chem 1972 37 669

3 Meek JS Org Syn Coll Vol 1973 V 126

4 Meyers AI J Org Chem 1979 44 3405

5 Augmiller JC Org Syn Coll Vol 1988 VI 179

編譯自：Organic Syntheses Based On Name Reactions, 3RdEd, A. Hassner, Page 108.