Ni- and Zn-promotion of γ-Al2O3 for the hydrolysis of COS under mild conditions

The seaweeds are bio-resource rich in sulfated and neutral polysaccharides. The tropical seaweed species used in this study (Solieria filiformis), after dried, shows 65.8% (w/w) carbohydrate, 9.6% (w/w) protein, 1.7% (w/w) lipid, 7.0% (w/w) moisture and 15.9% (w/w) ash. The dried seaweed was easily hydrolyzed under mild conditions (0.5 M sulfuric acid, 20 min.), generating fermentable monosaccharides with a maximum hydrolysis efficiency of 63.21%. Galactose and glucose present in the hydrolyzed were simultaneously fermented by Saccharomyces cerevisiae when the yeast was acclimated to galactose and cultivated in broth containing only galactose. The kinetic parameters of the fermentation of the seaweed hydrolyzed were Y(P⁄S) = 0.48 ± 0.02 g.g−1, PP = 0.27 ± 0.04 g.L−1.h−1, h = 94.1%, representing a 41% increase in bioethanol productivity. Therefore, S. filiformis was a promising renewable resource of polysaccharides easily hydrolyzed, generating a broth rich in fermentable monosaccharides for ethanol production.

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Hydrogen evolution from hydrolysis of ammonia borane catalyzed by Rh/g-C3N4 under mild conditions

International Journal of Hydrogen Energy ◽

10.1016/j.ijhydene.2018.02.148 ◽

2018 ◽

Vol 43 (14) ◽

pp. 7038-7045 ◽

Cited By ~ 23

Author(s):

Rui Lu ◽

Min Hu ◽

Caili Xu ◽

Yi Wang ◽

Yun Zhang ◽

...

Keyword(s):

Hydrogen Evolution ◽

Ammonia Borane ◽

Mild Conditions ◽

Hydrolysis Of

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ChemInform Abstract: Stereoselective Hydrolysis of Nitriles and Amides Under Mild Conditions Using a Whole Cell Catalyst.

ChemInform ◽

10.1002/chin.199341079 ◽

2010 ◽

Vol 24 (41) ◽

pp. no-no

Author(s):

T. BEARD ◽

M. A. COHEN ◽

J. S. PARRATT ◽

N. J. TURNER ◽

J. CROSBY ◽

...

Keyword(s):

Whole Cell ◽

Mild Conditions ◽

Stereoselective Hydrolysis ◽

Hydrolysis Of

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Selective Si–O–Si Bond Cleavage as Synthetic Access to Functionalized, Hydrolysis-stable Zinc Silanolates

Zeitschrift für Naturforschung B ◽

10.1515/znb-2009-11-1240 ◽

2009 ◽

Vol 64 (11-12) ◽

pp. 1558-s1579 ◽

Cited By ~ 8

Author(s):

Christian Däschlein ◽

Carsten Strohmann

Keyword(s):

Solid State ◽

High Stability ◽

Bond Cleavage ◽

Structural Studies ◽

Nmr Studies ◽

Molecular Systems ◽

Simple Treatment ◽

Mild Conditions ◽

Long Time ◽

Hydrolysis Of

The selective cleavage of the strong and poorly reactive Si-O-Si bond in functionalized siloxanes under mild conditions is a decisive task for modern synthetic chemistry. Simple treatment of the aminomethyl-functionalized disiloxanes 1, 6, (R,R)-7 and 8 ([R2(CH2NR')SiO]2, R =Me or Ph, NR'= NC5H10, NC5H8(CH3)2 or NC4H7(CH3)) with zinc(II) bromide and zinc(II) chloride, respectively, results in the formation of highly hydrolysis-stable, molecular zinc silanolates which were long time supposed to be unstable in the presence of water. Both, the selective cleavage of the Si-O-Si bond as well as the formation of the molecular zinc silanolates are independent of the substituents at silicon, the used zinc(II) salt or the aminomethyl side arm. Detailed structural studies showed that zwitterionic interactions are the reason for the high stability towards hydrolysis of the formed zinc silanolates 9, 10, (R,R)-11 and 12. NMR studies are indicative of the same structure of these molecular systems in solution as in the solid state

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Stereoselective hydrolysis of nitriles and amides under mild conditions using a whole cell catalyst

Tetrahedron Asymmetry ◽

10.1016/s0957-4166(00)80215-3 ◽

1993 ◽

Vol 4 (6) ◽

pp. 1085-1104 ◽

Cited By ~ 44

Author(s):

Timothy Beard ◽

Mark A. Cohen ◽

Julian S. Parratt ◽

Nicholas J. Turner ◽

John Crosby ◽

...

Keyword(s):

Whole Cell ◽

Mild Conditions ◽

Stereoselective Hydrolysis ◽

Hydrolysis Of

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Sequential pretreatment strategies under mild conditions for efficient enzymatic hydrolysis of wheat straw

Bioprocess and Biosystems Engineering ◽

10.1007/s00449-015-1355-1 ◽

2015 ◽

Vol 38 (6) ◽

pp. 1127-1141 ◽

Cited By ~ 10

Author(s):

Arturo Sanchez ◽

Juan Carlos Gil ◽

Oscar A. Rojas-Rejón ◽

Ana P. de Alba ◽

Andrea Medina ◽

...

Keyword(s):

Enzymatic Hydrolysis ◽

Wheat Straw ◽

Mild Conditions ◽

Sequential Pretreatment ◽

Hydrolysis Of

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Oxokohlenstoffe und verwandte Verbindungen. 32 [1]. Über die Umsetzung von Quadratsäuredichlorid und Perchlorcyclobutenon mit SchiffBasen

Zeitschrift für Naturforschung B ◽

10.1515/znb-2008-0701 ◽

2008 ◽

Vol 63 (7) ◽

pp. 1-7

Author(s):

Arthur H. Schmidt ◽

Peter Müllen ◽

Gabriele Wallmeyer ◽

Claudia Plutniok ◽

Peter R. Wiesert

Keyword(s):

Schiff Bases ◽

Good Yield ◽

Mild Conditions ◽

Hydrolysis Of

Squaric dichloride (3) reacts with Schiff bases 5 under mild conditions to give 1 : 1 adducts 7. On recrystallisation from alcohols, these adducts are converted to the respective N-(α-alkoxybenzyl)- squaric amide chlorides 8. The reaction has been extended to perchlorocyclobutenone 4. Thus, addition products 14 have been obtained from the reaction of 4 with Schiff bases 5, which, on recrystallisation from alcohols, afforded N-(α-alkoxybenzyl)-substituted 3-amino-2,4,4-trichloro-cyclobuten- 1-ones 15. Hydrolysis of the adducts 14 gave the aminotrichlorocyclobutenones 17 in good yield.

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Amide directed hydrocarboxylation of N-allylacetamide catalyzed by the aqueous Pd - tppts - Brønsted acid system (tppts = P(C6H4-m-SO3Na)3)1

Canadian Journal of Chemistry ◽

10.1139/v01-068 ◽

2001 ◽

Vol 79 (5-6) ◽

pp. 688-692 ◽

Cited By ~ 5

Author(s):

Göran Verspui ◽

Gábor Besenyei ◽

Roger A Sheldon

Keyword(s):

Substitution Reaction ◽

Aqueous Media ◽

Propanoic Acid ◽

Allylic Substitution ◽

Bronsted Acid ◽

Brønsted Acid ◽

Mild Conditions ◽

Brönsted Acid ◽

Acid Catalyzed ◽

Hydrolysis Of

The Pd - tppts - HOTs (tppts = P(C6H4-m-SO3Na)3, HOTs = p-toluenesulfonic acid) catalyzed hydrocarboxylation of N-allylacetamide in an aqueous medium afforded 4-acetamidobutyric acid and 3-acetamido-2-methylpropanoic acid under mild conditions, with a high regioselectivity towards the linear isomer. During the hydrocarboxylation an acid catalyzed hydrolysis of the amide moieties of both the substrate and the products took place, as well as the formation of acetamide and propanal, presumably via a Pd-catalyzed allylic substitution reaction of N-allylacetamide. The hydrolysis reaction was suppressed by lowering the amount of Brønsted acid cocatalyst (HOTs) or by employing a weaker Brønsted acid such as propanoic acid. The allylic substitution reaction was minimized by increasing the CO pressure but unfortunately this caused a decrease in the regioselectivity. A sudden inhibition took place after ca. 70% conversion, presumably caused by one of the side products. By increasing the tppts concentration to 13.1 mmol L-1 (20 equiv per Pd) the inhibition was circumvented and a quantitative conversion of N-allylacetamide was achieved.Key words: aqueous media, olefins, palladium, hydrocarboxylation, N-allylacetamide.

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