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Elucidate the structure of glucose....

Elucidate the structure of glucose.

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(i) Its moleculer formula is found to be `C _ 6 H_ (12) O _ 6 `. 
  (ii) On heating with HI it forms n-hexane suggesting that all the six carbon atoms are linked in a straight chain.
  ` overset(CHO) overset(|) underset(CH_2OH) underset(|) ((CHOH)_4) overset(HIDelta)to  underset("n  - hexane")(CH _3 - CH _2 - CH _2  - CH _2  - CH_ 2  - CH _3 ) ` 
  (iii) Glucose reacts with hydroxylamine to form an oxime. This show it contain carbonyl group.   
 `  overset(CHO)overset(|) underset(CH_2OH) underset(|)((CHOH)_4) overset(NH_2OH) to overset(CH= N -OH)overset(|) underset("Oxime")underset(CH_2OH) underset(|)((CHOH)_4)`
  (v)  In  pressure  of  bromine  water,  glucose  undergoes  oxidation  forming  gluconic  acid.  This  shows  carbonyl group  is  an  aldehyde group. 
  `  overset(CHO) overset(|) underset( CH_2 OH) underset(|) ((CHOH)_4) overset(Br_2 "water")to overset(COOH) overset(|)underset(CH_2OH) underset(|) ((CHOH) _4)`  
(v) Acetylation of glucose with acetic anhydride gives glucose penta acetate which confirms the presence of five OH groups. 
(vi) On oxidation with strong oxidising agent. like Cone. `HNO_3` it gives saccharic acid. This indicate the presence of   primary  alcoholic group. 
Based on the above facts Fischer gave open and ring structure for glucose. 
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