622 SCIENCE PROGRESS 



isobutyric acid rH 3 ^>CH . CO . OH amongst the products 



obtained when carefully purified crystalline specimens of 

 trimethyl carbinol, C(CH 3 ) 3 . OH, were oxidised by means of a 

 bichromate and sulphuric acid mixture. The formation of this 

 acid was a clear indication that the liquid contained, in addi- 

 tion to the original tertiary compound, a primary isobutyl 



alcohol £j^>CH.CH 2 . OH. 



That the two alcohols were closely related was already 

 evident from observations made six years previously. The 

 tertiary compound had been detected — as an impurity or as 

 a product of change — in commercial isobutyl alcohol after 

 conversion into the chloride (Annalen, 1867, 144, 34), and an 

 actual change from one alcohol into the other had been effected 

 (loc. tit. p. 30) by converting the tertiary alcohol by the action 

 of sulphuric acid (1 vol. to 2 vols, of water) into isobutylene, 

 combining this with hypochlorous acid and reducing out the 

 chlorine with sodium amalgam — 



CH 3 \ /OH CH 3 \ 



>C< -> >C = CH, 



CH/ \CHs CH 



Tertiary butyl alcohol Isobutylene 



CH a \ CH 3 \ 



-> >C.Cl.CH,.OH -> >CH.CH„.OH 



CH/ CH/ 



Isobutylene chlorhydrin Isobutyl alcohol 



A more direct conversion of the isobutylene into a butyl 

 alcohol, by absorbing it in sulphuric acid (2 vols, to 1 vol. 

 water), diluting and distilling, had led to the reproduction of 

 the original tertiary compound as the main product of the 

 action (loc. tit. p. 22), but no method was available for the ready 

 separation of the non-crystalline primary isomeride, and no 

 attempt was therefore made at the time to detect it as a minor 

 constituent of the resulting alcohol, although the possibility 

 of its formation was clearly recognised. When, however, it 

 was found in 1873 that its presence in the products of inter- 

 action of tertiary butyl alcohol and sulphuric acid could be 

 demonstrated by its ready oxidation to isobutyric acid, it was 

 at once evident that its formation must be ascribed to a 

 reversible dehydration of the alcohol followed by recombination 



