5- -y-valerolactone

These trivial names are permitted -y-butyrolactone, -y-valerolactone, and 5-valerolactone. Names based on heterocycles may be used for all lactones. Thus, -y-butyrolactone is also tetrahydro-2-furanone or dihydro-2(3/f)-furanone. 

Valence shell electron pair repulsion theory, 1, 564 Valence tautomerism photochromic processes and, 1, 387 y-Valerolactone, o -allyl-a -2-(pyrido[2,3-6]-imidazolyl)-synthesis, 5, 637 Validamycin A as fungicide, 1, 194 Valinomycin... 

In the reaction of a-sulfonyl carbanion with lactones, the corresponding hydroxy-co-ketosulfones were obtained " . Thus, various o-hydroxyketones were shown by Umani-Ronchi and coworkers to be formed from the corresponding lactones. For example, the reaction of a, a-dilithioalkyl phenyl sulfones with lactones in THF at low temperatures afforded co-hydroxy-jS-ketosulfones which, upon desulfonylation with aluminium amalgam, gave the corresponding hydroxyketones . This process was applied for the syntheses of cis-jasmone and dihydrojasmone by treating y-valerolactone with ds-3-hexen-l-yl phenyl sulfone and n-hexyl phenyl sulfone. ... 

Ring-opening polymerization of a-methyl-substituted medium-size lactones, a-methyl-y-valerolactone and a-methyl-c-caprolactone, proceeded by using lipase CA catalyst in bulk [82]. As to (R)- and (S)-3-methyl-4-oxa-6-hexa-nolides (MOHELs), lipase PC induced the polymerization of both isomers. The apparent initial rate of the S-isomer was seven times larger than that of the R-isomer, indicating that the enantioselective polymerization of MOHEL took place through lipase catalysis [83]. 

Levulinic acid is obtained by hydrolysis of cellulose-containing biomass. R D is actively conducted at DuPont Co. to employ levulinic acid for the synthesis of pyr-rolidones (solvents and surfactants), a-methylene-y-valerolactone [monomer for the preparation of polymers similar to poly(methyl methacrylate)], and levulinic acid esters (fuel additives) [26]. 

Reduction of lactones leads to cyclic bemiacetals of aldehydes. With a stoichiometric amount of lithium aluminum hydride in tetrahydrofuran at —10° to —15° and using the inverse technique, y-valerolactone was converted in 58% yield to 2-hydroxy-5-methyl tetrahydrofuran, and a-methyl-5-caprolac-tone in 64.5-84% yield to 3,6-dimethyl-2-hydroxytetrahydropyran [1028]. Also diisobutylaluminum hydride in tetrahydrofuran solutions at subzero temperatures afforded high yields of lactols from lactones [7024]. 

This compound on bromination, followed by hydrolysis of the ester group with hydrobromic acid and removal of carbon dioxide, gave a-brom-S-chlor-y-valerolactone, from which by treatment with ammonia 7-oxyproline was obtained —... 

Mosby, W. L. Die FriEdel-Crasi s-Reaktion mit y-Valerolacton. I. Die Syn-these verschiedener Polymethylnaphthaline. J. Amer. chem. Soc. 74, 2564 (1952). 

Levulinic acid. Hydrogenation of levulinic acid resulting in the reduction of the ketone moiety leads to 4-hydroxy pentanoic acid. This acid can cyclize to form y-valerolactone (GVL) which is a useful industrial solvent. A 94% yield of GVL was obtained with a Raney nickel catalyst, and a hydrogen pressure of 5 MPa at a temperature of 100-150... 

Figure 20. Simultaneous enantiomer separation of various classes of compounds ( Schurig test mixture 184) on CP-Cyclodextrin-/3-2,3,6-M-19 (permethylatcd /3-cyclodextrin in OV-1701) [25 m x 0.25 mm (i.d.) column, 70°C for 5 min followed by 3cC/miu, 0.65 bar hydrogen]143. 1+2 2,6,6-trimethylbicy-clo[3.1.1]hept-2-ene (x-pinene), 3 ( + )-(lJR)-//ms-2,6,6-trimethylbicyclo[3.1. l]heptane (pinane), 4 (-)-(lS )-fra/M-pinanc. 5 (-)-(lS)-fw-pinane, 6 ( + )-(l/J)-cw-pinane, 7 + 8 2,3-butancdiol. 9 meso-2,3-butanediol, 10 + 11 tetrahydro-5-methyl-2-furanone (y-valerolactone). 12 + 13 1-phenylethanaminc. 14 + 15 1-phenylethanol, 16 + 17 2-ethylhexanoic acid.

Some representatives of y-lactones are y-valerolactone 150, y-decalactone 151 with peach-like flavour, (Z)-6-dodecen-4-olide 152, 3-methyl-4-octanolide (whiskey lactone) 153 and 3-hydroxy-4,5-dimethyl-2(51T)-furanone (sotolone) 154 (Structure 4.46), found in fenugreek, coffee and sake [1-4, 21-23, 62]. 

The base peak (m/z 56) of y-valerolactone and the same strong peak of butyrolactone probably arise as follows ... 

LC/ESI-MS analyses were applied to determine urinary glucuronidated and sulfated tea catechins after the administration of green tea to humans, mouse and rats [109]. The major conjugates were identified as monoglucuronides and monosulfates of EGC and EC. Besides these metabolites, also G-methyl-EGC-G-glucuronides, O-sulfates and O-methyl-EC-O-sulfates in human urine were detected. Furthermore, the ring-fission metabolites of EGC and (-)-epicatechin, 5-(3 ,4 ,5 -trihydroxyphenyl)-y-valerolactone and 5-(3 ,4 -dihydroxyphenyl)- valerolactone respectively, have been detected in the monoglucuronide and monosulfate forms. 

Uracil, p268 5-Ureidohydantoin, a77 Urethane, e91 Valeraldehyde, p27 Valeric acid, p36 y-Valerolactone, p40 Valerone, d531 Valeronitrile, p33 Valeryl chloride, p44 Valinols, a213, a214... 

Major metabolite 3-HPPA minor metabolites 4-HPPA, 5-(3-hydroxyphenyl)-y-valerolactone, 5-(3,4-dihydroxyphenyl)-y-valerolactone and HPVA 5-(3,4-Dihydroxyphenyl)-y-valerolactone... 

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