- 158 - 



Carvone. In continuation of earlier work *■) on cyanodihydrocarvone, 

 A. Lapworth studied jointly with E. Wechsler 2 ) the behaviour of 

 this compound towards amyl nitrite and sodium ethylate. The product 

 of this reaction, a body melting at 138 to 139 , is not, however, the 

 isonitroso derivative to be expected, but a lactame of the formula 



/NH 

 C 10 H 13 ON<^ I . When treated with aqueous hydrogen bromide at 



low temperature, it is converted into an isomeric lactame of the 

 m. p. 180 . The first-named body is split up by 10 per cent, caustic soda 

 liquor into an amido acid of the m. p. 155 , which, however, forms back 

 the lactame on heating in vacuo, or on boiling with glacial acetic acid 

 or acetic acid anhydride. The methyl ester of the acid is solid, and 

 melts at 99 to ioo°. If the lactame of the m. p. 139 remains for 

 several days in contact with concentrated hydrochloric acid, there is 

 formed a lactone base ^ TTT 



/ NH 2 



C 10 H 14 ON< 



J >co 



I q/ 



of the m. p. 122 to 123 . The lactame of the m. p. 180 , when 

 treated in the same manner, also yields a lactone base of the m. p. 157 

 to 1 5 8°, isomeric with the former. A methylated lactame is obtained 

 when methyl iodide and sodium methylate are allowed to act on the 

 lactame of the m. p. 139 at the temperature of the water-bath. From this 

 there results, on saponifying with 10 per cent, caustic lye, the methyl- 



7 NH.CH 3 

 ated amido acid CaEoON; of the m. p. 155 . Strong 



\C00H 

 hydrochloric acid converts the latter in the cold into the methyl lactone base 



7 NH.CH 3 

 C 10 H 14 ON< 



>co 



I 0/ 



of the m. p. 129 to 130 . Dilute sulphuric acid converts the last- 

 named base on application of heat, with loss of methylamine, into a 

 lactone acid 



c 10 h 16 o 2 n/ 



>co 

 I 0/ 



of the m. p. 66 to 67 . This acid is identical with the one of the 

 m. p. 70 to J2° formed on hydrolysis of the lactone base by means 



1 ) Journ. chem. Soc. 89 (1906), 955, 1819, 1869; Report October 1906, 132; 

 April 1907, 152. 



2 ) Ibidem 91 (1907), 977. 



