Furfural Furfuryl Mercaptan

Furfural comes from pentose sugars in cereal straws and brans. Furfural is the precursor of furfuryl mercaptan and its disulfide, difurfuryl disulfide, which are both important chemicals for coffee, meat and roasted flavours. They are prepared by the reaction of furfural and hydrogen sulfide (Scheme 13.15). 

Furfuryl mercaptan cannot be prepared according to the classical method using furfuryl chloride and potassium sulfide.2 It has been prepared by reduction of 2-furfuryl disulfide, obtained from furfural and ammonium hydrosulfide.3 The mercaptan has also been obtained in 33% yield 2 by the reaction of furfuryl chloride with thiourea and subsequent decomposition of the intermediate S-2-furfurylisothiourea according to the general method described in Organic Syntheses.4 In the present method, which has been published previously, the use of the very unstable and difficultly available furfuryl halides is avoided.6... 

Freon-114, d227 2,5-Furandione, m2 2-Furanmethanol, f46 Furfural, f39 2-Furfuraldehyde, f39 Furfuryl mercaptan, f44 Furoic acid, f42 Furylacrylic acid, f41 2-Furyl methyl ketone, a44... 

Some of these reaction flavors occur in nature. The oxidation of mercaptans to form disulfides and other products is in part responsible for the loss of flavor from fresh roasted coffee only a short time after brewing. Furfiiryl Mercaptan is one of the most potent flavor components in coffee and is responsible for a fresh brewed coffee flavor. While it is present at only 1.55 ppm versus Furfuryl Alcohol (515 ppm) and Furfural (157 ppm), its flavor contribution is 310,014 times its flavor threshold (0.005 ppb). If there were a 100% conversion of Furfuryl Mercaptan to Diflirfuryl Disulfide, the coffee would appear to be 10 times weaker due to Difurfliryl Disulfide s flavor threshold being 0.05 ppb, or ten times weaker than Furfuryl Mercaptan (equation 10). The overall effect of this oxidation is that the coffee has lost its flavor. 

Stoll et al. (1967) prepared it by reaction of furfuryl mercaptan with furfuryl bromide, giving a crystalline product. Tressl and Silwar obtained it by reaction of furfural with cysteine under roasting conditions. 

CAS 98-02-2 EINECS/ELINCS 202-628-2 UN 1228 (DOT) UN 3071 (DOT) FEMA 2493 Synonyms 2-Furanmethanethiol Furfural mercaptan 2-Furfuryl mercaptan a-Furfuryl mercaptan a-Furfuryl mercaptan Furfuryl thiol 2-Furylmethanethiol 2-Furylmethyl mercaptan Empirical CsHeOS... 

Furyl methanal. See Furfural 2-Furylmethanethiol. See Furfuryl mercaptan (2-Furyl) methanol. See Furfuryl alcohol 2-Furylmethyl butanoate. See Furfuryl butyrate 2-Furyl methyl ketone. See 2-Acetylfuran... 

FurFuryl alcohol 202-627-7 Furfural QO Furfural 202-628-2 Furfuryl mercaptan 202-634-5 Benzotrichloride 202-637-1... 

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