Grignard Eeagent on Camphoric and Isocamphoric Esters. 5 



Dipheiiyloxycampliolic acid obtained by the hydrolysis of 

 diphenylcampholide, being a r-oxy-acid, should easily yield a 

 lactone, as was in fact found to be the case. A small quantity of 

 the acid was weighed in a platinum boat, and kept in an air-bath 

 at 100° until the constant weight was attained. It was then 

 analysed: — 



0-2339 gave 0-7009 CO., and 0-1587 H,0. 0=81-73 ; H = 7.41. 

 OvÄA requires 0=82-45 ; H=7-56 per cent. 



Thus by merely heating to 100°, the lactone was formed. The 

 same result was also obtained by heating the acid with an excess 

 of acetic anhydride on a water-bath for about five hours. 



The action of fuming nitric acid : — Diphenylcampholide dissolves 

 easily in fuming nitric acid with a considerable evolution of heat. 

 On the addition of water to the solution, brownish precipitates 

 separated out. A chloroform solution of the precipitates was boiled 

 with animal charcoal, filtered, and the filtrate was evaporated on a 

 water-bath. Small yellowish crystals melting at 224-225°, easily 

 soluble in chloroform, and insoluble in alcohol, ether, and 

 petroleum ether, were thus obtained, which gave the following 

 results on analysis: — 



0.1275 gave 0-2997 CO, and 0-0531 H,0. 0=64-11 ; H=4-66. 

 0-1873 gave 11-12 c.c. N. at 760 mm. and 18°C. N = 6-82. 

 C,.,H2AN2 requires 0=64-36 ; H=5-41 ; N = 6-83 per cent. 



Thus the substance is dinitrodiphenylcampholide. 



Diphenylcampholide is very stable toward the action of 

 oxidising agents. Thus even when it was heated with chromic 

 acid mixture to 150-155° for about twenty hours, only a very small 

 portion of the substance was attacked, and, on repeated recrystal- 

 lisation from alcohol, a small quantity of a substance melting at 



