Iodine → 1,1-Bis-(3-methoxyphenyl)ethene

Participants

Reaction Steps

5.28 g (20 mmoles) of 1,1-bis(3-methoxyphenyl)ethanol are dissolved in 30 mL of glacial acetic acid. A catalytical amount of iodine is added and the solution refluxed for about 5-15 minutes or until the dehydration is complete. The progress of the reaction is monitored by TLC on silica (5% EtOAc in hexanes). The burgundy red solution is diluted with water (100 mL) and the product extracted with ether (2-3 extractions with 10 mL portions). The combined ethereal extracts are washed consecutively with water (into which a spatula tip of sodium metabisulfite was added) and 10% sodium carbonate, dried over anh. K2CO3 and evaporated to yield 4.63 g (96%) of the title compound. 1H NMR (CDCl3): 6.8-7.3 (m, ArH, 8H), 5.45(s, C═CH2, 2H), 3.75 (s, OCH3, 6H).

Provenance & Evidence