Carbohydrates erythritol

In addition to these physical studies at the Bureau, Tipson was able to return to his synthetic interests, both alone and in collaboration with other staff members. He was especially pleased to prepare D-talose in crystalline form, an accomplishment that had eluded Emil Fischer. Pursuing his longstanding interest in the reaction of sulfonic esters with iodide and following an earlier observation that the tetratosyl ester of erythritol is converted into butadiene by the action of sodium iodide and zinc, he demonstrated (with A. Cohen) that nonterminal unsaturation may be conveniently introduced into alditol derivatives by reaction of contiguous secondary sulfonates with sodium iodide and zinc dust in boiling A.A-dimethylformamide. This Tipson-Cohen reaction subsequently proved of great utility in other hands for the conversion of more complex carbohydrate structures into vicinal dideoxy derivatives. 

In a series of papers, Kent and coworkers reported on the synthesis of the racemic 2-fluorotetritols and 2-fluoropentitols, and related carbohydrates from simple, non-carbohydrate precursors containing a fluorine atom in the carbon chain. Thus, synthesis of 2-deoxy-2-fluoro-DL-erythritol (537) and its threo isomer (538) was accomplished303 by vigorous reduction of ethyl ethoxalylfluoroacetate (536) with lithium... 

Further experiments disproved Wohl s theories1-3 4 as to a direct condensation mechanism. By degradation of 2,3,4,5-tetra-O-acetyl-L-arabinononitrile82 (5) in the presence of propionamide or benzamide, l,l-bis(acetamido)-l-deoxy-L-erythritol (6) was obtained in yields comparable to those obtained when the reaction was conducted in the absence of these extraneous amides. Also, an excess of acetamide in the medium did not increase the formation of nitrogenated carbohydrate derivatives. 

Allyl Ethers of Carbohydrate. A number of compds, such as allyl glycerol, allylglycol, allyl mannitol, allylsorbitol, all yl pent a-erythritol, etc were prepd during and after WWII by Nichols Yanovsky. They also discussed previous work on this subject and listed several refs. According to them the first compd of this type was triallyl-glycerol prepd in 1856 by M.Berthelot S. de Luca... 

Most of the dimeric material that has been found82- 84 in y-irradiated, deoxygenated aqueous solutions of carbohydrates might be formed by way of reaction 23, especially at low-Tadical, -steady-state conditions, where reaction 6 is of great importance. However, except for ethylene glycol19 and erythritol,22 it has not yet been possible to characterize the dimeric material in sufficient detail. 

The second zone also contains carbohydrate opportunities, exemplified by, e.g., glycolic [73,104], pyruvic [105], lactic [74], and acrylic acids as well as glyoxal, glycolaldehyde [72, 106], acetic acid [71], erythritol [70], and y-valerolactone [47, 77]. A petrochemical route to these chemicals could be derived (e.g., the route to lactic acid via hydrolysis of acrylonitrile [107]), but in general, the carbohydrate route is likely to be cost-competitive. Glyoxal, acetic acid, and... 

Table 1 shows the separation of alcohols (2,3-butanediol, ethanol, methanol), glycols (glycerol), alditols (erythritol, arabitol, sorbitol, galactitol, mannitol), and carbohydrates (rhamnose, arabinose, glucose, galactose, lactose, sucrose, raffinose, maltose) using a CarboPac MAI column set with 480 mM sodium hydroxide eluent... 

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