100103-52-4Relevant academic research and scientific papers
Synthesis of Alkyl-2,3-dihydrothienofurans, Aroma Compounds of Coffee
Gorzynsky, Marek,Rewicki, Dieter
, p. 625 - 637 (2007/10/02)
Starting with 3,4-dihalofurans 1 and using furyllithium compounds as intermediates the 3-halo-4-(2-haloethyl)furans 3, 8-10, and 14 are synthesized.They are transformed into the corresponding 3-lithio-4-(2-haloethyl)furans which react with sulfur at -80 deg C to form lithium-3-thiolates and cyclize spontaneously at higher temperature to afford the 2,3-dihydrothienofurans 4, 11, and 15.By this reaction sequence 2,3-dihydro-6-methylthienofuran (kahweofuran) (4c), a roasting aroma component of coffee, is synthesized in 12percent overall yield.Eight mono-, di-, and trialkyl-substituted 2,3-dihydrothienofurans, its sulfoxide 5 as well as 4-formyl derivative 16 and the 4-methoxycarbonyl derivative 17 of kahweofuran are described.
