Fischer cyanohydrin synthesis

This reaction was first reported by Kiliani in 1885, and then extended by Fischer in 1889. It is the conversion of an aidose into two one-carbon-higher epimeric homologs, which involves a nucleophilic addition of a cyanide to the terminal carbonyl group of an aldose, hydrolysis of cyanohydrin, and reduction of the resulting lactone. Therefore, it is known as the Kiliani synthesis, Kiliani-Fischer reaction, Kiliani cyanohydrin synthesis, Kiliani-Fischer synthesis, Kiliani-Fischer cyanohydrin synthesis, Fischer-Kiliani cyanohydrin synthesis, or cyanohydrin reaction. This reaction is carried out under alkaline conditions (e.g., at pH > 9.1) to maintain a high effective concentration of cyanide... 

The present method is adapted from Fischer employing recently developed modifications of the cyanohydrin synthesis. - ... 

C. S. Hudson, The Fischer Cyanohydrin Synthesis and the Configurations of Higher-carbon Sugars and... 

Lemieux and Spohr (Alberta) here trace our understanding of enzyme specificity in broad perspective as they assess Emil Fischer s lock and key concept advanced a century ago in relation to current ideas of molecular recognition. It may be noted that the very first article in Volume 1 of Advances, by Claude S. Hudson, was devoted to the Fischer cyanohydrin synthesis and the consequences of asymmetric induction. 

It is of some historical interest that Kiliani s cyanohydrin synthesis (24) enabled Emil Fischer (25) to carry out the first asymmetric synthesis. Lapworth (26) used this base-catalyzed nucleophilic 1,2-addition reaction in one of the first studies of a reaction mechanism. Bredig (27,28) appears to have been the first to use quinine (29) in this reaction as the chiral basic catalyst. More recently, others (20) have used basic polymers to catalyze the addition of cyanide to aldehydes. The structure of quinine has been known since 1908 (30). Yet it is of critical importance that Prelog s seminal work on the mechanism of this asymmetric transformation (eq. [4]) could not have begun (16) until the configuration of quinine was established in 1944 (31,32). 

The free nitriles of iV-methyl-L-glucosaminic acid and iV-methyl-L-mannosaminic acid have been prepared by Wolfrom, Thompson and Hooper by the Kiliani-Fischer cyanohydrin synthesis. 

L-Mannitol has been prepared by the reduction of L-mannosaccharo-dilactone or L-mannose. By far the most convenient procedure is that used by Baer and Fischer for their preparation of L-glyceraldehyde by the oxidative cleavage of l,2 5,6-diisopropylidene-L-mannitol with lead tetraacetate. L-Arabinose was converted to L-mannonolactone by the cyanohydrin synthesis and this was hydrogenated over platinum oxide to the desired L-mannitol. High hydrogen pressures, rather than low as usually employed with this catalyst, were used. 

Among the classic methods for the extension of the aldose chain by one carbon atom from the reducing end [9J, the Kiliani-Fischer cyanohydrin synthesis [10] is a milestone in carbohydrate chemistry. However after 110 years from discovery and numerous applications [11], including the preparation of carbon and hydrogen isotopically labeled compounds for mechanistic and structural studies [12], there are still several drawbacks that make the method impractical. These are the low and variable degree of selectivity and the harsh reaction conditions that are required to reveal the aldose from either the aldonic acid or directly from the cyanohydrin. Synthetic applications that have appeared in recent times confirmed these limitations. For instance, a quite low selectivity was registered [13] in the addition of the cyanide ion to the D-ga/acfo-hexodialdo-l,5-pyranose derivative 1... 

How, M. J., Brimacombe, J. S., and Stacey, M., The Pneumococcal Polysaccharides, 19, 303-357 Hudson, C. S., Apiose and the Glycosides of the Parsley Plant, 4, 57-74 Hudson, C. S., The Fischer Cyanohydrin Synthesis and the Configurations of Higher-carbon Sugars and Alcohols,... 

The synthesis of D-psicose as a colorless sirup ([< ]% + 3.1° in water) by Steiger and Reichstein13 may be regarded as the first authentic preparation of this ketohexose. The Kiliani-Fischer cyanohydrin synthesis furnished D-allonic lactone (VII) from D-ribose. This lactone, on reduction with sodium amalgam, gave D-allose (VIII) which was transformed into D-psicose (I) by refluxing with pyridine. Pyridine had been introduced into the Lobry de Bruyn-Van Ekenstein reaction by Fischer, Danilov and their coworkers.13 ... 

Film, cellulose acetate, I, 300 cellulose ester, I, 325 starch acetate, I, 297 Fischer cyanohydrin synthesis of higher-C sugars, I, 1-38... 

THE FISCHER CYANOHYDRIN SYNTHESIS AND THE CONFIGURATIONS OF HIGHER-CARBON SUGARS AND ALCOHOLS... 

XL Improvements in the Details of the Fischer Cyanohydrin Synthesis of Higher-... 

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