ALCOHOLS 69 



AMYL ALCOHOLS. C 3 H n OH. 



Eight isomers are possible, all of which are known : 



B.P. Sp. Gr. at 20. 



1. Normal primary, CH 3 . CH 2 . CH 2 . CH 2 . CH 2 OH 138 -817 



CH 3x 



2. Isobutyl carbinol, ^CH . CH 2 . CH 2 OH 130 -810 



CH 3 / 



3. Secondary butyl carbinol, /CH . CH 2 OH 128 -816 



CH 3 CH/ 



-4. Tertiary butyl carbinol. 



(primary) CH 3 C . CH 2 OH u 3 



CHg^ 



5. Methyl propyl carbinol, CH 3 



(secondary) >CHOH 119- 



CH 3 . CH 2 . CH./ 



112 -819 



CH 3 .CH 2 



7. Diethyl carbinol, \ C HOH 



(secondary) CH 3 . CH 2 / 



5. Dimethyl ethyl carbinol, CH 3 C . OH 102' 



(tertiary) CH 3 . CH 2 / 



Secondary butyl carbinol contains an asymmetric carbon atom (see 

 lactic acid) and consequently exists in a dextro- and a laevo-form. 

 Together with primary isobutyl alcohol and propyl alcohol the two 

 amyl alcohols, isobutyl carbinol and laevo-secondary butyl carbinol, are 

 the principal constituents of fusel oil and they together constitute 

 fermentation amyl alcohol. 



The fusel oil from potatoes or cereals contains chiefly isobutyl 

 carbinol, secondary butyl carbinol being present only to 13-22 per 

 cent. The fusel oil from beet molasses contains 48-58 per cent, of 

 secondary butyl carbinol. 



Fermentation amyl alcohol is a strongly refractive liquid which 

 boils at 130-131 and is very slightly soluble in water 3-3 volumes 

 in loo volumes of water at 22. Its vapours, on being inhaled, produce 

 a peculiar sensation in the head, causing headache, etc. The two 

 alcohols cannot be separated by fractional distillation, but only by 

 chemical means. The mixture generally referred to as amyl alcohol is 

 frequently used as a solvent. 



