The acid-catalyzed hydrolysis of methyl 2-chloro-2-deoxy-β-<scp>D</scp>-glucopyranoside

Buncel, Erwin; Bradley, Paul R.

doi:10.1139/v67-087

Cited by 15 publications

(5 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…1,3,4,6-Tetra-O-acetyl-2-deoxy-2-fluoro-D-glucopyranose (11) and 1,3,4,6-tetra-O-acetyl-2-deoxy-2-fluoro-D-mannopyranose (12) were heated with N HCl at 70°C to give fully deprotected 2-deoxy-2-fluoro-a,b-D-glucose (1) and 2-deoxy-2-fluoro-a,b-D-mannose (2), respectively (see Tables 1 and 2 In the last step of such a deacetylation reaction, the strong inorganic acid must be neutralized, generally with barium or silver carbonates. 23,24 To increase the practicality of the process, reduce the cost, and avoid a prolonged filtration step, we successfully used sodium carbonate. Simple treatment of the reaction mixture with a stoichiometric amount of Na 2 CO 3 , followed by evaporation of water and column chromatography, gave us the pure deprotected products 1 and 2.…”

Section: Synthesis Of 2-deoxy-2-fluoro-d-glucose and 2-deoxy-2-fluoromentioning

confidence: 99%

d-Glucose- and d-mannose-based antimetabolites. Part 2. Facile synthesis of 2-deoxy-2-halo-d-glucoses and -d-mannoses

Fokt

Szymański

Skóra

et al. 2009

Carbohydrate Research

View full text Add to dashboard Cite

Section: Synthesis Of 2-deoxy-2-fluoro-d-glucose and 2-deoxy-2-fluoromentioning

confidence: 99%

d-Glucose- and d-mannose-based antimetabolites. Part 2. Facile synthesis of 2-deoxy-2-halo-d-glucoses and -d-mannoses

Fokt

Szymański

Skóra

et al. 2009

Carbohydrate Research

View full text Add to dashboard Cite

“…The high reactivity of 1 is due in part to the fact that this compound exists in a twist boat conformation (see 1 ‘), which increases the reactivity of this donor compared to those in the normal chair conformation . The lack of oxygenation at C(6) also increases the reactivity of the anomeric center. , In contrast, all other glycosyl donors that adopt the normal 4 C 1 conformation and/or have deactivating heteroatom substituents at C(6) required much higher glycosidation reaction temperatures, as illustrated by the glycosidation reaction of 2 and 4 . One additional complication with the use of glycosyl acetates such as 4 is that under the reaction conditions the β-glycosyl acetates equilibrate with the α-acetate anomers, which are considerably less reactive as glycosylating agents.…”

mentioning

confidence: 99%

2-Deoxy-2-iodo- and 2-Deoxy-2-bromo-α-glucopyranosyl Trichloroacetimidates: Highly Reactive and Stereoselective Donors for the Synthesis of 2-Deoxy-β-glycosides

1999

View full text Add to dashboard Cite

[formula: see text] 2-Deoxy-2-iodo- and 2-deoxy-2-bromoglucopyranosyl trichloroacetimidates 8-10 and 22 are extremely useful precursors of 2-deoxy-beta-glycosides. These reactive glycosyl donors undergo highly stereoselective glycosidation reactions at -78 degrees C with a range of glycosyl acceptors using TBS-OTf as the activating agent. beta-Glycosides are obtained with > or = 19:1 selectivity in six of the seven examples reported herein.

show abstract

“…Our present work concerns the iilvestigation of synthetic routes to 2,2-dichloro substitution of hexopyranose structures. Electronegative substitution at this position is of particular interest to us in kinetic studies of the 1 acid hydrolysis of glycopyranosides (4).…”

mentioning

confidence: 99%

Studies with halogeno sugars. II. A stable free glycosyl chloride

Bradley¹,

Buncel²

1968

Can. J. Chem.

Self Cite

View full text Add to dashboard Cite

Dehydrochlorination of 3,4,6-tri-O-acetyl-2-chloro-2-deoxy-~-~-glucopyranosyl chloride with diethyla~nine yielded 3,4,6-tri-0-acetyl-2-chloro-D-glucal. The latter was further chlorinated to 3,4,6-tri-0-acetyl-2-deoxy-2,2-dichloro-~-~-urubino-hexopyranosy chloride, which on deacetylation provided the first example of a stable, free glycopyranosyl chloride.A 3,4,6-tri-0-acetyl-2-chloro-2-deoxymannopyranosyl chloride, also isolated in this work, was characterized by properties which correspond closely to the recently reassigned anomer.Canadian Journal of Chemistry, 46, 3001 (1968) Although moilohalogen substitution on asymmetric carbon atoms of cyclic sugars has been achieved in ilumerous instances (1) and with each of the four halogens, cyclic sugars with gemdihalogen substitution on ring carbons are comparatively rare. The earliest examples appear to be acetylated 2-deoxy-2,2-dichloro-D-erythropentopyranose and its glycosyl chloride, synthesized by Vargha and Kuszmann (2). More recently Brown and Jones (3) have reported a 3-deoxy-3,3-di-iodo derivative of D-ribo-hexo-1 furanore. Our present work concerns the iilvestigation of synthetic routes to 2,2-dichloro substitution of hexopyranose structures. Electronegative substitution at this position is of particular interest to us in kinetic studies of the 1 acid hydrolysis of glycopyranosides (4). IA long-established route to 2-chlorodeoxy substitution of hexopyranoses has been via chlorination of the 1,2-glycals to 2-chlorodeoxy-D-glycosyl chlorides. In the earliest investigation of this reaction Fischer, Bergmann, and Schotte (5) passed chlorine into a cold solution of tri-0-acetyl-D-glucal (1) in carbon tetrachloride and obtained a product described as 'triacetylglucal dichloride'. Recent investigations of this substance using modern analytical techniques show that it is a mixture of gluco (2) and n7anno (3) epimers. Lemieux and Fraser-Reid (6), using nuclear magnetic resonance spectroscopy 1 (n.m.r.), reported the a-D-gluco dichloride as the main product in greater than 80% yield, but did not detect the manno dichloride. Subsequently I Lefar and Weill (7) subjected a crystalline sample I of the dichloro-triacetyl-glycal to thin-layer chromatography (t.1.c.) and showed that it was a mixture of two major components which they identified by n.m.r. as the a-D-gluco and a-Dmanno dichlorides in a ratio of roughly 4 : 1. The results of the present work are qualitatively similar to those of Lefar and Weill, as far as the ratio of the two compoilents is concerned, but the minor component exhibits significantly different physical properties and n.m.r. spectrum (vide infra). Very recently, since the completion of our work, Igarashi, Honma, and Imagawa have reported (8) mainly by a four-centered transition state or a concerted mechanism, which is in contrast to the two-stage oxocarbonium mechanism proposed by . In 1963 Vargha and Kuszmann (2) reported a series of reactions leading from 3,4-di-0-acetyl-D-arabinal to an acetylated 2,2-dichloro-2-deoxy-D-pentose. Chlorinatio...

show abstract

The acid-catalyzed hydrolysis of methyl 2-chloro-2-deoxy-β-D-glucopyranoside

Cited by 15 publications

References 9 publications

d-Glucose- and d-mannose-based antimetabolites. Part 2. Facile synthesis of 2-deoxy-2-halo-d-glucoses and -d-mannoses

d-Glucose- and d-mannose-based antimetabolites. Part 2. Facile synthesis of 2-deoxy-2-halo-d-glucoses and -d-mannoses

2-Deoxy-2-iodo- and 2-Deoxy-2-bromo-α-glucopyranosyl Trichloroacetimidates: Highly Reactive and Stereoselective Donors for the Synthesis of 2-Deoxy-β-glycosides

Studies with halogeno sugars. II. A stable free glycosyl chloride

Contact Info

Product

Resources

About