Branched-chain sugars. Reaction of 1,2:5,6-di-O-isopropylidene-α-D-ribo-hexofuranos-3-ulose with sodium cyanide and methyl nitroacetate

1976 ◽  
Vol 54 (4) ◽  
pp. 543-547 ◽  
Author(s):  
Alex Rosenthal ◽  
B. L. Cliff
Keyword(s):  
Acetic Anhydride ◽  
Sodium Cyanide ◽  
Equimolar Amount ◽  
Anhydrous Ethanol ◽  
Toluenesulfonic Acid ◽  
Methyl Nitroacetate ◽  
Branched Chain ◽  
Acetate Derivative

Treatment of 1,2:5,6-di-O-isopropylidene-α-D-ribo-hexofuranos-3-ulose (1) with sodium cyanide in anhydrous ethanol followed by addition of an equimolar amount of methyl nitro-acetate gave 3-C-cyano-1,2:5,6-di-O-isopropylidene-α-D-glucofuranose (2) in 57% yield. When methyl nitroacetate was first added to sodium cyanide in alcohol followed by the addition of ketose 1 then the allo-cyanohydrin epimer 4 was produced in 85% yield. 3-C-(Carbomethoxy-R,S-nitromethyl)-1,2:5,6-di-O-isopropylidene-α-D-allofuranose (6) was produced in low yield in the latter reaction and was isolated and characterized as its 3-O-acetate derivative 7. Selective acetolysis of the 5,6-O-isopropylidene group of the branched-chain sugars was achieved using acetic anhydride and p-toluenesulfonic acid monohydrate. The proof of structure of the cyano-hydrins is described.

scholarly journals Unusual Reaction of Azoxybenzenes withp-Toluenesulfonic Acid in Acetic Anhydride

1982 ◽  
Vol 55 (5) ◽  
pp. 1538-1542 ◽  
Author(s):  
Ichiro Shimao ◽  
Ken Fujimori ◽  
Shigeru Oae
Keyword(s):  
Acetic Anhydride ◽  
Unusual Reaction ◽  
Toluenesulfonic Acid

p-Toluenesulfonic acid functionalized imidazole ionic liquids encapsulated into bismuth SBA-16 as high-efficiency catalysts for Friedel–Crafts acylation reaction

2021 ◽  
Author(s):  
Guofang Gao ◽  
Qian Zhao ◽  
Cheng Yang ◽  
Tingshun Jiang
Keyword(s):  
Ionic Liquids ◽  
Acetic Anhydride ◽  
Mesoporous Materials ◽  
High Efficiency ◽  
Strong Acid ◽  
Acylation Reaction ◽  
Acid Properties ◽  
Composite Catalysts ◽  
Toluenesulfonic Acid

Four imidazole ionic liquids acidified with p-toluenesulfonic acid were loaded on Bi-SBA-16 mesoporous materials to obtain four composite catalysts with strong acid properties. They were applied to acylation reaction of anisole and acetic anhydride.

Reactions of nitro sugars. IX. The synthesis of branched-chain dinitro sugars by Michael addition

1968 ◽  
Vol 46 (15) ◽  
pp. 2511-2517 ◽  
Author(s):  
Hans H. Baer ◽  
K. S. Ong
Keyword(s):  
Michael Addition ◽  
Diethyl Malonate ◽  
Side Chain ◽  
Methyl Nitroacetate ◽  
Branched Chain ◽  
Sugar Derivatives ◽  
Asymmetric Carbon

The reaction of methyl 2-O-acetyl-4,6-O-benzylidene-3-deoxy-3-nitro-β-D-glucopyranoside (1) or of methyl 4,6-O-benzylidene-2,3-dideoxy-3-nitro-β-D-erythro-hex-2-enopyranoside (2) with nitroalkanes led to branched-chain dinitro sugar derivatives, namely methyl 4,6-O-benzylidene-2,3-dideoxy-3-nitro-2-nitroalkyl-β-D-glucopyranosides (3). The nitroalkanes employed included nitromethane, nitroethane, 1-and 2-nitropropane, and methyl nitroacetate. The three first-mentioned nitroalkanes were added in similar fashion to methyl 4,6-O-benzylidene-2,3-dideoxy-3-nitro-β-D-threo hex-2-enopyranoside (5) to give methyl 4,6-O-benzylidene-2,3-dideoxy-3-nitro-2-nitroalkyl-β-D-galactopyranosides (6). Analogous reactions of 1 and 5 with diethyl malonate produced the corresponding branched-chain glycosides 7 and 8. The reactions appear to be highly stereoselective as far as the configurations at C-2 and C-3 in the products are concerned. However, there is evidence for the formation of side-chain epimers in three cases where the nitroalkyl side chain possesses an asymmetric carbon.

PREPARATION OF SOME NEW BRANCHED-CHAIN CARBOHYDRATES FROM D-α-FRUCTOHEPTONIC LACTONE

1954 ◽  
Vol 32 (4) ◽  
pp. 404-414 ◽  
Author(s):  
R. J. Woods ◽  
A. C. Neish
Keyword(s):  
Nitric Acid ◽  
Hydrochloric Acid ◽  
Hydrogen Chloride ◽  
Sodium Borohydride ◽  
Periodic Acid ◽  
Equimolar Amount ◽  
Glassy Material ◽  
Sodium Amalgam ◽  
Aldonic Acid ◽  
Branched Chain

D-α-Fructoheptonic lactone (I) was oxidized with an equimolar amount of periodic acid to give formaldehyde and a hexuronic lactone (II) which was hydrolyzed to crystalline 4-C-hydroxymethyl-L-xyluronic acid (III), (68% yield). Hydrogenation of III gave an aldonic acid which was isolated as crystalline 2-C-hydroxymethyl-L-xylonic lactone (V). Reduction of V by sodium amalgam gave 2-C-hydroxymethyl-D-xylose (VI), which crystallized after purification as the 2,5-dichlorophenylhydrazone. Hydrogenation of VI gave 1,1-di(C-hydroxymethyl)-D-threitol (VII) which was purified as the crystalline hexaacetate. Treatment of III with methanolic hydrogen chloride gave a glassy material which was reduced by sodium borohydride and hydrolyzed by hydrochloric acid to give 4,4-di(C-hydroxymethyl)-D-threose (IX), which was isolated and characterized as the crystalline 2,5-dichlorophenylhydrazone. Oxidation of III by either bromine or nitric acid gave 2-C-hydroxymethyl-D-xylaric acid (IV), which was characterized as the crystalline ammonium salt.

scholarly journals Reactions of 4-hydroxycoumarin with heterocyclic aldehydes

2021 ◽  
Vol 9 (3) ◽  
Author(s):  
Renáta Gašparová ◽  
Katarína Kotlebová ◽  
Margita Lácová
Keyword(s):  
Acetic Acid ◽  
Acetic Anhydride ◽  
Microwave Irradiation ◽  
Sodium Hydroxide ◽  
Acid Medium ◽  
Sodium Acetate ◽  
Toluenesulfonic Acid ◽  
Heterocyclic Aldehydes

Reactions of 4-hydroxycoumarin 1 with heterocyclic aldehydes 2-4 led to bis-4-hydroxycoumarin derivatives 5-7 under microwave irradiation as well as under the classical heating. The subsequent reactions of products 5-7 are described. 4,4’-Epoxydicoumarins 8, 9 were prepared by the reaction of 5-7 in acetic acid / p-toluenesulfonic acid medium. Compound 10 was prepared by the reaction of 5 in acetic anhydride in the presence sodium acetate. Dioxocine-1,15-dione 11 was prepared by the reaction of 6 with dichloromethane in sodium hydroxide-toluene.

Determination of Pentachlorophenol in Natural and Waste Waters

1974 ◽  
Vol 57 (2) ◽  
pp. 389-393 ◽  
Author(s):  
Alfred S Y Chau ◽  
John A Coburn
Keyword(s):  
Aqueous Solution ◽  
Liquid Chromatography ◽  
Acetic Anhydride ◽  
Reliable Method ◽  
Gas Liquid Chromatography ◽  
Sewage Effluent ◽  
Waste Waters ◽  
Acetate Derivative ◽  
Potassium Carbonate Solution

Abstract A sensitive and reliable method suitable for routine determination of pentachlorophenol (PCP) in natural and waste waters is reported. PCP is extracted from the preserved sample with benzene and from the benzene into a potassium carbonate solution. The addition of acetic anhydride to the aqueous solution produces the acetate derivative of PCP, which is extracted in hexane and analyzed by electron capture gas-liquid chromatography. The analysis of PCP in lake water and sewage effluent is presented, along with the retention times of 17 other phenolic acetates. By this procedure, as little as 0.01 ppb PCP in 1 L water can be determined.

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