524. Sugar nitrates. Part V. Removal of nitrate groups

Abstract

Sugar Nitrates. Part V . 2587hydrate in the presence of Raney nickel,3 palladium-charcoal,4 or copper or iron p ~w d e r , ~ but for sugar nitrates a catalyst is generally unnecessary. The method enables a nitrate group to be removed selectively from a compound also containing toluene-9-sulphonate, methanesulphonate, methyl, or benzyl groups.The 2 : 3-dinitrates of methyl 4 : 6-O-ethylidene-a-~-glucoside and its anomer, and of methyl 4 : 6-0-benzylidene-a-~-glucoside are partially reduced when boiled in ethanol for 3-6 hours with 1.2 moles of hydrazine hydrate per mole of dinitrate. From each dinitrate, equal amounts of the two mononitrates and a little starting compound were obtained. Thus the reaction proceeds equally readily for each nitrate group and is independent of the nature of the 4 : 6-acetal grouping and of the configuration of the methyl group. This method makes such 2-nitrates available for the first time, although a low yield of methyl 4 : 6-O-benzylidene-a-~-glucoside %nitrate has been obtained through migration of the nitrate group from CO) to C(z).6 Proof that migration of nitrate does not occur during the reactions with hydrazine was obtained by boiling methyl 4 : 6-O-ethylidene-a-~glucoside 3-nitrate with an equimolecular proportion of hydrazine hydrate in ethanol for 3 hours : unchanged starting compound (31 %) and methyl 4 : 6-O-ethylidene-a-~-glucoside (43%) (but no %nitrate) were isolated. The reaction of methyl 4 : 6-O-ethylidene-a-~glucoside 2-nitrate was similar.Sugar acetates, benzoates, and benzenesulphinates, esterified on primary or secondary alcoholic groups, are converted into the alcohols on being boiled with hydrazine hydrate in ethanol for 90 minutes. Methyl 4 : 6-O-benzylidene-a-~-glucoside was obtained from its 2 : 3-diacetate, and acetamide and 1 : 2-3 : 5-di-O-methylene-~-glucose from the 6-acetate. This shows that fission of the oxygen-carbon bond takes place during deacetylation. Benzoyl groups are removed more slowly; for example, after 90 minutes' boiling, 1 : 2-5 : 6-di-0-cyclohexylidene-~-glucose 3-benzoate was recovered (52%) together with 1 : 2-5 : 6-di-0-cycZohexylidene-~-glucose (31%) and benzamide (14%). After 14 hours'

Decomposition of nitrate esters to alcohols

“…Registry No.-3-Nitraza-l,5-pentanediol, 13084-48-5. methoxydihydromenthofuran (2). However, they1 did not conclusively identify their C10H14O2 product and merely considered it to have the ketoaldehyde structure 1 in analogy to the formation of ß-acetylacrolein (3)2 in the hydrolysis of 2,5-dimethoxy-2,5-dihydrosylvan (4).2-5 1 2 3…”