96 



POLYHYDRIC ALCOHOLS 



[46 A-48. 



with hydrogen bromide (Ge'romont, 

 Ann. 158, 370; Reboul, Ann. Chim. 

 [5] 14, 472; Lermontoff, Ann. 182, 

 358 Erlenmeyer, Ber. 12, 1354 ; Ann. 

 197, 184; Roth, Ber. 14, 1351 ; Bogo- 

 molitz, Bull. Soc. [2] 30, 23) and con- 

 version into the glycol by the action of 

 moist silver oxide, or by forming the 

 diacetate and hydrolysing (Reboul, loc. 

 cit. 491 ; Beilstein and Wiegand, Ber. 



15, 1497; Zander, Ann. 214, 178; 

 Niederist, Monats. 3, 839). The hydro- 

 lysis is best effected by barium or 

 calcium hydroxide (Henry, Bull. Acad. 

 Roy. Belg. [3] 36, 9). 



Or from glycerol through allyl 

 alcohol (ethyl alcohol [14; G]), the 

 monochlorhydrin by combination with 

 hypochlorous acid, and reduction with 

 sodium amalgam (Henry, Rec. Tr. Ch. 



16, 208). 



47. Isobutylene Glycol ; 

 2-Methyl-2 ; 3-Propauediol. 



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



NATURAL SOURCE. 



Among the products of fermentation 

 of saccharose by Saccharomyces ellip- 

 soideus (Claudon and Morin, Comp. 

 Rend. 1O4, 1109; Bull. Soc. [2] 49, 

 178; Henninger and Sanson, Comp. 

 Rend. 106, 208). 



SYNTHETICAL PROCESSES. 



[A.] From isobutyl alcohol [18] 

 through isobutylene (tertiary butyl alco- 

 hol [19 ; B]), the bromide (2-methyl-2 : 

 3-dibrompropane) by combination with 

 bromine (Linnemann, Ann. 162, 36), 

 and decomposition of the bromide by 

 heating with potassium carbonate solu- 

 tion (Nevol6, Bull. Soc. [2] 27, 63; 

 Comp. Rend. 83, 6$; 146). 



Isobutylene bromide can also be 

 obtained from isobutyl alcohol by heat- 

 ing isobutyl chloride or bromide with 

 bromine in the presence of iron (Meyer 

 and Miiller, Journ. pr. Ch. 46, 161 ; 

 Herzfelder, Ber. 27, 1 260). The glycol 

 can be prepared also direct 1 iso- 



butyl alcohol by the action o~ n s) 



hydrochloric acid (Lwoff, Bull. Soc. [2] 

 43, 112). 



Isobutylene gives this glycol by 

 oxidation with potassium permanganate 

 (Wagner, Ber. 21, 1232). Isobutylene 

 bromide is also converted into the glycol 

 by heating with water and lead oxide 

 to 50 (Krassusky, Journ. Russ. Soc. 

 33, 791). 



[B.] From tertiary butyl alcohol [19] 

 through isobutylene (see under isobutyl 

 alcohol [18 ; A]), and then as under 

 A above. Or by conversion into tertiary 

 butyl chloride or bromide and then into 

 isobutylene bromide by heating with 

 bromine and iron (Herzfelder, loc. cit, 

 1261 : see also Meyer and Miiller, 

 Journ. pr. Ch. 46, 161). 



Also from tertiary butyl alcohol 

 through isobutylene bromide by the 

 action of bromine (fitard, Comp. Rend. 

 114, 753), and then as under A. 



NOTE : All generators of isobutylene given 

 under isobutyl [18] and tertiary butyl alcohol 

 [19] are generators of this glycol. These are: 

 isoamyl alcohol [18 ; B] ; isovaleric acid [18 ; C] ; 

 acetone and glycerol or acetic acid via /3-dimethyl- 

 acrylic acid [18 ; C], &c. 



48. Glycerol ; 1:2: 3-Propanetriol. 

 CH 2 (OH) . CH(OH) . CH 2 (OH) 



NATURAL SOURCES. 



Widely distributed in vegetable and 

 animal kingdoms, glyceryl esters of 

 acids of the fatty and other series being 

 found in most saponifiable fats and 

 fixed oils (Scheele, 1779, Crell's Ch. 

 Journ. 4, 190 ; CrelFs Ch. Ann. 1, 99 ; 

 Chevreul, ' Recherches sur les Corps, 

 Gras J ; Pelouze, Ann. 19, 210 ; 20, 

 46; Comp. Rend. 21, 718: for list of 

 oils and fats see A. H. Allen's tables 

 in Thorpe's 'Dictionary of Applied 

 Chemistry/ III, 28-34). 



Glyceryl esters occur also in certain 

 waxes, such as Japan wax from Rhus 

 succedanea and other species, the wax 

 from species of Balanophora (Java), 

 myrtle-berry wax from Myrica cerifera 

 (N. America), and other species of 

 '-a found in N. and S. America, 

 ^~j ~~xjia, and the Cape of Good Hope. 



