- 178 — 



Nerol. Zeitsche *) has previously advanced the view that nerol is a 

 stereoisomeride and not a structural isomeride of geraniol. Definite proof 

 of the correctness of this theory has now been supplied by Blumann and 

 Zeitschel 2 ) by the oxidative resolution of nerol by Tiemann and Semmler's 

 method. In the course of this process acetone and lsevulic acid were 

 formed from nerol in the same quantitative proportions as from geraniol. 

 The nerol used in the experiment had been prepared from oil of Helichrysum 

 angustifolium and possessed the following constants: b. p. 225 to 226°, 

 di5o 0,8815, a D + 0°, m. p. of the diphenylurethane 52 to 53°. The alcohol 

 had first been oxidised with potassium permanganate solution and after- 

 wards with chromic acid and sulphuric acid. 



CH 3 

 CH S 



CH 3 



CH 3 j 

 CH • CH 2 • CH 2 ■ C =4= CH • CH 2 OH Oxidation 



Nerol or Geraniol. 



CH 3 

 CO + H0C0CH 2 CH 2 C0 + HOCOCOOH 



CH 3 



Acetone. Laevulic acid. Oxalic acid. 



Menthol. Several years ago Brunei 3 ) showed that thymol was ca- 

 pable of being reduced to hexahydrothymol by Sabatier and Senderens' 

 method. The complicated mixture which results from this conversion has 

 been examined by R. H. Pickard and W. O. Littlebury 4 ), who have isolated 

 from it several isomeric menthols and menthones, as well as l-methyl-3- 

 ci/cZohexanol. The thymol which had remained unchanged in the reduction- 

 process was removed from the reaction-product by treating with soda-liquor. 

 After heating the mixture with phthalic anhydride in order to separate the 

 alcohols, the ketones were isolated by means of semicarbazide. By re- 

 peated recrystallisation from 95% acetic acid the authors succeeded in 

 separating two acid phthalates (m. p. 175 to 177° and 129 to 131° re- 

 spectively), from the acids of the phthalic ester. The separation of the 

 two esters is much facilitated when the dilute aqueous solution of the 

 sodium salts is treated with magnesium chloride. The magnesium salt 

 of the one ester is thereby precipitated in the form of a sparingly soluble 

 compound which, after being recrystallised from alcohol, melts between 

 119 and 122°. When resolved with hydrochloric acid it yields the acid 

 phthalic ester with m. p. 129 to 131°. When chloride of zinc is added to 

 the filtrate of the magnesium salt, the zinc salt of the ester, m. p. 175 



*) Berl. Berichte 39 (1906), 1780; Report October 1906, 124. 

 a ) Berl. Berichte 44 (1911), 2591. 



3 ) Compt. rend. 140 (1905), 252; Report April 1905, 103. 



4 ) Journ. chem. Soc. 101 (1912), 109. 



