¥ acids. eiteiceck: the amide ‘of pulegenic acid is unsuitable for the preparation 
a us dihydropulegenic amide*), m. p. 150 to 151° which can be hydrolyzed into the acid. 
‘A far more convenient method for preparing the free saturated acid is to abstract 
, nd to. reduce and then “saponify the unsaturated ester. The free dihydropulegenic acid 
> 3 D ai ined from the ester boils at 139° (12 mm,). ‘Eykman®), too, noe arrived at. this” Ae 
y reducing pulegenic acid with nickel and ‘hydrogen. é : 
‘s ce styl derivate of which melted at 132°. 
ady years ago, had recognized the identity of D, l-dihydrocaryenolide’ with dihydro- 
?p ee Dihydrocarvenolide is difficult to hydrolyze; better than with ordinary 
alcoholic potash it is split up. with amylalcoholic potash- into a hydroxy derivative of 
ag BacHic apliey m. p. 150 to 151°. plies ee are 
ee fo az me) Gs acid. Sogalay He Ease 
eek fk 
Be yp conn as es a i COsH 7 On COsH A io 
i 7 ie GEM ee a. rae 
ease (Ill) a neg 2 : (V) Ee CUD) 
The different cyclic isomerides of puleeenic acid. 
ecm 
tr OF 
) COLH 
ty Ber eae ' Nitrogenous Bodies. 
3 The cyclylmethylamines (CH2)x>>CH- CHy- NH, show the tendency to ai when 
reated with ser Sit TOs not only the” eauiveponcigs alcohols, but also, with a 
Br x r 
4) Liebig’s egfalen 379 (1911), 213; 381- (1911), 78; 392 (1912), 57; imepore April 1911, 184; October 1911, 
); April. 1913, 149. — *) Ibidem 296 (1897), 261. —- *) Described in Liebig’s Annalen- 392 (1912), 58; Report 
(9, 149. — *) Chem. Zentralbl. 1941, I. 1030. — *) Liebig’s Annalen 300 (1898), 262; 881 (1911), 69: 
a 495 5 October 1898, 52; October 191t, 126; vee 1913, 149. 
\ 
10 
“SN 
: ao lee ceucecnic acid. lt is far more adenine to isomerize lbaeuaer acid 
cid is “decomposed Sith: qarmation of paieseke oa carbon dioxide, Ae obienet 5 
1 nodification, however, boiling with slight decomposition between 256 and 260°. The 
% amide of this acid adds hydrogen easily, in presence of colloidal. palladium, yielding < 
2 ydrogen chloride from hydrochloropulegenic ester by heating with an organic base : 
Z For obtaining pulegenic acid, also carvone ‘may be. used as primary material which PER. 
transformed, vid dihydrocarvenolide, into hydrochloropulegenic ester. Wallach®), So eee 
On heating. dihydropulegenic amide with bromine and alkali Shae is formed, the eS 
ee d ihydrocarvenolic acid. On reducing the amide of this acid Wallach obtained dihydro- s oe 
