Furfural reduction

N. Kostesha, J.R.M. Almeida, A. Heiskanen, B. Hahn-Hagerda, M.-F. Gorwa-Grauslund and J. Emneus, Electrochemical probing of in vivo 5-hydroxymethyl furfural reduction in saccharomyces cerevisiae. Analytical Chemistry, In Press. 

Keto and 5-keto aldonic acids also give carbon dioxide and furfural (see below) in yields similar to those for the uronic acids. However, ascorbic acid, as discussed later, gives a very high yield (above 80%) of furfural. Reductic acid, an enolic substance similar in structure to the ascorbic... 

Manufacturing. Almost all the THE in the United States is currendy produced by the acid-catalyzed dehydration of 1,4-butanediol [10-63-4]. Only one plant in the United States still makes THE by the hydrogenation of furfural (29). Du Pont recendy claimed a new low cost process for producing THE from / -butane that they plan to commercialize in 1995 (30—32). The new process transport-bed oxidizes / -butane to cmde maleic anhydride, then follows with a hydrogen reduction of aqueous maleic acid to THE (30). 

Furylcarbinol has been prepared by the reduction of furfural with sodium amalgam but the Cannizzaro reaction is the better practical method of preparation. 

Esters of diphenylacetic acids with derivatives of ethanol-amine show mainly the antispasmodic component of the atropine complex of biologic activities. As such they find use in treatment of the resolution of various spastic conditions such as, for example, gastrointestinal spasms. The prototype in this series, adiphenine (47), is obtained by treatment of diphenyl acetyl chloride with diethylaminoethanol. A somewhat more complex basic side chain is accessible by an interesting rearrangement. Reductive amination of furfural (42) results in reduction of the heterocyclic ring as well and formation of the aminomethyltetrahydro-furan (43). Treatment of this ether with hydrogen bromide in acetic acid leads to the hydroxypiperidine (45), possibly by the intermediacy of a carbonium ion such as 44. Acylation of the alcohol with diphenylacetyl chloride gives piperidolate (46). ... 

The finely divided lead produced by reduction of the oxide with furfural vapour at 290°C is pyrophoric and chemically reactive. 

According to the submitters, methyl amyl ketone (800 g.) and ammonia (600 cc.) have been converted to 2-aminoheptane, b.p. 139-141°, in exactly the same manner, in 50-55 per cent yields. A slightly modified procedure was used in the preparation of w-heptylamine and furfurylamine. Heptaldehyde (320 g.) was dissolved in 500 cc. of methanol, and 150 cc. of liquid ammonia was added the reduction was conducted as above. w-Heptyla-mine, b.p. 57-58°/23 mm., was obtained in yields of 53-63 per cent. Freshly distilled furfural (290 g.) was dissolved in 500 cc. of methanol, 150 cc. of liquid ammonia was introduced, and the reduction carried out as usual. The product was removed, filtered, and fractionated directly. Furfurylamine, b.p. 144-146°, was obtained in 50 per cent yield. 

Furfural. Furfural is readily obtainable from dehydration of pentoses. Reduction of furfural can lead to a variety of products that are more volatile, more stable and possibly also more useful than furfural itself. Selective reduction of the aldehyde moiety leads to furfuryl alcohol (Scheme 15), whereas further reduction of the furan core will lead to tetrahydrofurfuryl alcohol. Reductive deoxygenation can result in the formation of either 2-methylfuran or 2-methyltetrahydrofuran, which can be used as liquid fuels or solvents. 

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... 

Bel skii328 succeeded in converting furfural and furfurylidene acetaldehyde into pyrrole at 300° and pyrrolidine homologs at 200°, by reductive amination on Raney nickel, which was followed by rearrangement in the gas phase, in the presence of Pt ... 

A catalytic, enantioselective approach towards the synthesis of polyol chains has recently been reported by Carreira et al. and has been applied in a synthesis of the polyol subunit of amphotericin B (Scheme 5) [13]. Aldol addition of the silyl dienolate 26 to furfural (27) catalyzed by the Tol-BlNAP-CuF -complex (2 mol-%) gives rise to the addition product 28 in 95 % yield and >99 % ee after one recrystallization. Spectroscopic evidence indicates that a copper dienolate is formed in situ from the silyl dienolate 26 and is actually the active nucleophile [14], Standard transformations including a j-yw-selective reduction of the ft-hydroxy ketone by the method of Prasad and the oxidative conversion of the furan ring to the car-... 

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