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All 7 posts | Subject: prep. of gamma-valerolactone from hexose sugars | Please login to post | Down | |||||
Vitus_Verdegast (Hive Addict) 05-14-04 20:49 No 507191 |
prep. of gamma-valerolactone from hexose sugars (Rated as: excellent) |
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A bottle of freshly prepared levulinic acid from paper mill sludge Preparation of levulinic acid from hexose sugars Levulinic acid is a major product of the controlled degradation of hexose sugars by acids. Because the supply of hexoses from cellulose-containing plant material is immense and replenishable, conversion of such materials into a single chemical product meets one of the requirements for a basic chemical raw material. The reactive nature shown by the keto and carboxyl groups meets the second requirement. Although levulinic acid has been known since the 1870's, when many of its reactions were first established, it has never reached commercial use in any significant volume. Hexoses are convertible to levulinic acids by essentially a process of dehydration and cleavage of a mole of formic acid. The theoretical yield from a hexose is 64.5%, but the literature as reviewed by Wiggings (Advances in carbohydrate chem 4, 306-314 (1950)) shows that only about two thirds the theoretical yield can be attained; the balance proceeds to insoluble residues. Substantially the same yields from cellulose in Douglas fir sawdust were amply demonstrated by Frost and Kurth in 1951 (Tappi 34, 80-86 (1951); C.A. 45, 4441). Formation of levulinic acid from low-cost cellulosic products overcomes one of the major difficulties encountered in other processes. The preparation of levulinic acid from carbohydrates by the action of mineral acids is known from G. J. Mulder (J. Prakt. Chem. 21, 219 (1840) cited in Patent US5189215). Early work on levulinic acid involved reacting different carbohydrate sources with mineral acids. Levulinic acid has been produced by the action of acids on carbohydrates such as: - glucose; - galactose and sucrose Wiggins, "Utilization of Sucrose" (Advance in Carbohydrate Chemistry, 4, 306-314 (1949)) Thomas, et al., "Studies on Levulinic Acid. I. Its Preparation from Carbohydrates by Digestion with Hydrochloric Acid Under Pressure" (J.S.C.I. Jun. 8, vol 53, 2324-2328 (1931)); - fructose, glucosamine, chitose, sorbose, deoxypentoses, and hexose Patent US3258481 Patent US2206311; - cane sugar and starch Patent US2270328; - disaccharide and polysaccharide unions Wiggins, "Utilization of Sucrose" (Advance in Carbohydrate Chemistry, 4, 306-314 (1949)). Here is the procedure from Organic Syntheses coll vol 1 p 335: http://www.orgsyn.org/orgsyn/buttons.asp?showprint=1&prep=cv7p0034
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Vitus_Verdegast (Hive Addict) 05-14-04 22:03 No 507202 |
1,4-butanediol from levulinic acid ??? | |||||||
"1,4-butanediol dinitrates and butanetriols are obtained by Pb anode oxidation of levulinic acid" Fichter, Fr. and Herndl, J. Helv. Chim. Acta 25, 229-240 (1942); C.A. 36, 5713 http://www.geocities.com/eric_vornoff/government_is_your_friend.jpg |
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Barium (Heavyweight Chempion(eer)) 05-14-04 22:21 No 507204 |
Damn | |||||||
That is really OTC!! BTW, I told you several times not to post those old pics of me. Especially not the ones showing my red ears. How am I ever going to be able to seduce Aztec now?? Severe Aztecoholic and President of Sooty's fanclub - Sooty for President!! |
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Vitus_Verdegast (Hive Addict) 05-14-04 23:33 No 507213 |
easy | |||||||
Shave off the moustache, and give her say 3 grams of gamma-valerolactone . Also, she was very fond of my red ears.. BTW ning, I saw you were looking for a malonic acid preparation recently. You might want to check this out: "Malonic acid is obtained by treatment of levulinic acid with ozone." Nakazaki, M. J. Japan Chem. Soc. 3, 108-110 (1949); C.A. 46, 6288 http://www.geocities.com/eric_vornoff/government_is_your_friend.jpg |
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Captain_America (Hive Bee) 09-11-04 10:14 No 530834 |
Pushing GHB 100% OTC | |||||||
Can't get more uncontrolable than sugar, Prohibition Church's worst nightmare is reality, GREAT POST Dr. Vitus! Only downside seems these reductions that are not OTC. Guess what, sodium dithionit redeuce levulinic acid in acceptable yields, see Post 497065 (Ganesha: "dithionite aldehyde/ketone reductions part II", Novel Discourse) |
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lugh (Moderator) 09-15-04 01:19 No 531353 |
Literature Located (Rated as: good read) |
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The following articles/abstracts have been located, scanned and uploaded J. Am. Chem. Soc. 71, 122-125 (1949) C.A. 43, 5367 J. Am. Chem. Soc. 71, 3245-46 (1949) J. Am. Chem. Soc. 48, 3163-65 (1926) Chemistry is our Covalent Bond |
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moo (Hive Addict) 09-15-04 06:16 No 531402 |
Meerwein-Ponndorf-Verley reduction (aluminium... | |||||||
Meerwein-Ponndorf-Verley reduction (aluminium isopropoxide, which is OTC) should work with the free acid, unless it forms insoluble salts, then the next options would be using a salt or an ester of levulinic acid. fear fear hate hate |
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