3- hydroxymethyl-2 -furanone

The reaction between the chiral furanones (/ )-/3-angelica lactone 129 (Z = H) and 5-hydroxymethyl-2(5//)-furanone 143 (Z = OH) with cyclopentadiene was... 

PHOTOINDUCED-ADDITION OF METHANOL TO (5S)-(5-0-tert-BUTYLDIMETHYLSILOXYMETHYL)FURAN-2(5H)-ONE (4R,5S)-4-HYDROXYMETHYL-(5-0-tert-BUTYLDIMETHYLSILOXYMETHYL)FURAN-2(5H)-ONE (2(5H)-Furanone, 5-[[[(1,1-dimethylethyl)dimethylsilyl]oxy]methyl]-, (S)-and D-erythro-Pentonic acid, 2,3-dideoxy-5-0-[(1,1-dimethylethyl)dimethylsilyl]-3-(hydroxymethyl)-, y-lactone)... 

Thermolysis of D-fructose in acid solution provides 11 and 2-(2-hydrox-yacetyl)furan (44) as major products. Earlier work had established the presence of 44 in the product mixtures obtained after acid-catalyzed dehydrations of D-glucose and sucrose. Eleven other products were identified in the D-fructose reaction-mixture, including formic acid, acetic acid, 2-furaldehyde, levulinic acid, 2-acetyl-3-hydroxyfuran (isomaltol), and 4-hydroxy-2-(hydroxymethyl)-5-methyl-3(2//)-furanone (59). Acetic acid and formic acid can be formed by an acid-catalyzed decomposition of 2-acetyl-3-hydroxyfuran, whereas levulinic acid is a degradation prod-uct of 11. 2,3-Dihydro-3,5-dihydroxy-6-methyl-4//-pyran-4-one has also been isolated after acid treatment of D-fructose.The pyranone is a dehydration product of the pyranose form of l-deoxy-D-eo f o-2,3-hexodiulose. In aqueous acid seems to be the major reaction product of the pyranone. 

By GC-MS analysis, peaks 36, 37 and 39 were estimated to be 3-hydroxy-4,5-dimethyl-2(5H)-furanone, acetate of hydroxymethyl furfural and 4-pentyl-2-pentenolide, respectively. At this stage, the sample was too small to apply other analytical methods therefore, we tried to synthesize all the possible compounds using the synthetic approaches described in the following section. None of thethree synthetic products showed the characteristic sugary aroma that we had recognized in each separated fraction however, the yield of fraction 11-GC TRAP from molasses was calculated to be ca. 

SYNS ALMOCARPINE (3S-cis)-3-ETHYLDIHYDRO-4-((l-METHYL-lH-IMIDAZOD5-YL)METHYL)-2(3H)-FURANONE a-ETHYL-p-(HYDROXYMETHYL)-l-... 

Similarly prepared is (4R,5R)-dihydro-3,4-dihydroxy-3-hydroxymethyl-5-(lriphenylmethy oxymethyl)-2(3H)-furanone yield 80% d.r. [(3S)/(3R)] 88 12. 

The intramolecular aziridination of alkoxycarbonyl azides derived from ( )-5-hydroxymethyl-2(5//)-furanone, via thermal decomposition to nitrenes, gave the tricyclic compound 34 which was successively converted to the bicyclic compound 35. The aziridine ring opening with hydrazoic acid/ sodium azide ion of the aziridines 34 and 35 gives azido lactones 36 with the xylo configuration mixtures of xylo- and (y.w-forms were obtained by partial epimerization in equilibrating conditions and were easily separated60. 

Preparative Methods both enantiomers of dihydro-5-(hydroxymethyl)-2(3H) furanone and their trityl derivatives are commercially available but expensive. The simplest and by far most popular method for preparing (5)-dihydro-5-(hydroxymethyl)-2(3H)-furanone (2) consists of enantiospecific deamination of L-glutamic acid and subsequent selective reduction of the resulting carboxylic acid (13) (eq 1). Purification of the intermediate acid (13) by crystallization and not by distillation is recommended in order to secure an excellent optical yield (>98% ee). Likewise, (f )-dihydro-5-(hydroxymethyl)-2(3//)-furanone (1) (>98% ee) can be obtained from o-glutamic acid. As the latter is considerably more expensive than its natural antipode, an appealing option is to convert the (5)-lactone into its enantiomer (eq 2)P Also available and equally useful is an inversion route to (f )-dihydro-5-(trityloxymethyl)-2(3H)-furanone (5) by way of the Mitsunobu reaction (eq 3). ... 

Synthetic Applications. (5 )-Dihydro-5-(hydroxymethyl)-2(3H)-furanone (2) was first described in 1971 as an intermediate in the synthesis of o-ribose from r-glutamic acid. Since then, this lactone and its (f )-enantiomer have found widespread use as chirons for constructing a rich variety of natural products ranging from simple pheromones to complex macrocycles and ionophore antibiotics. The chemical manipulation of these chirons often involves lactone cleavage at an early stage, - - as illustrated by the preparation of suitable intermediates for the synthesis of the Vespa orientalis pheromone (R)-S-n-hexadecanolactone (14) (eq 4), the antiviral fungal metabolite brefeldin A (15) (eq 5), and (7aa)-cp/-hemibrevetoxin B (16) (eq 6). ... 

Related Chirons. The commercially available (/ )-(—)- and ( -(+)-enantiomers of 5-hydroxymethyl-2(5H)-furanone (22 and ent-22) and their various protected derivatives have also been extensively used in the synthesis of natural products," nucleosides, and other bioactive substances. - A cost-effective, versatile route to these chirons is illustrated by the preparation of (22) (eq 12). ... 

Related Reagents. iV-Benzyloxycarbonyl-L-serine p-Lactone a,3-Butenolide -y-Butyrolactone Dihydro-5-(hydroxymethyl)-2(3//)-furanone p-Ethynyl-p-propiolactone 3-Propiolactone. 

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