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Helferich method acid synthesis

However, another application of the Fischer-Helferich method clearly exhibits its limitations. Long chain alkyl glycosides have gained interest as nonionic surfactants. Their technical synthesis is based on acid catalysis of the reaction between glucose and alcohol. Due to the inherent solubility problems, typical drawbacks of the Fischer-Helferich method are encountered the technical product consists of a mixture of different anomers and, due to the fact that excess alcohol cannot be used for solubilization of the reaction mixture, reaction of glucose with itself is also found. [Pg.37]

The nitriles can also be employed as intermediates in the condensation of ethyl glyoxylate with aJdehydo sugars under the influence of sodium methoxide, leading to the preparation of L-ascorbic acid and similar compounds. Helferich and Peters described the synthesis of D-ascorbic acid (XXVIII) from tetraacetyl-n-xylononitrile (XXVI) presumably the nitrile underwent a type of ZempMn degradation and the n-threose (XXVII) thus formed condensed with the glyoxylic ester. The method... [Pg.128]

See other pages where Helferich method acid synthesis is mentioned: [Pg.285]    [Pg.480]    [Pg.453]    [Pg.34]    [Pg.35]    [Pg.35]    [Pg.49]    [Pg.480]    [Pg.119]    [Pg.35]    [Pg.35]    [Pg.49]    [Pg.170]    [Pg.23]    [Pg.136]    [Pg.138]    [Pg.171]    [Pg.158]    [Pg.45]    [Pg.127]    [Pg.590]    [Pg.176]    [Pg.232]    [Pg.577]    [Pg.170]    [Pg.158]    [Pg.34]    [Pg.146]   
See also in sourсe #XX -- [ Pg.98 ]



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