14.10: Enumerate the reactions of D-glucose which cannot be explained by its open chain structure.
(2) The pentaacetate of glucose does not react with hydroxylamine. This indicates that a free −CHO group is absent from glucose.
(3) Glucose exists in two crystalline forms − andβ. The -form (m.p. = 419 K) crystallises from a concentrated solution of glucose at 303 K and the β-form (m.p = 423 K) crystallises from a hot and saturated aqueous solution at 371 K. This behaviour cannot be explained by the open chain structure of glucose.