therefore these yield is about 3 4 times that of the japanese patent publication no 24094 1969 which no formation of adipic acid was recognized at the photochemical reaction of the other references furthermore it should be noted that the yield of cyclohexylnitrate increased remarkably depend on the ratio of oxygen to nitrogendioxide in particular as the molar ratio of cyclohexane to oxygen was stoichiometric 300 ml pyrex glass tube was degassed in which 100 u03bc cyclohexane 10 cc or 20 cc nitrogendioxide and 50 cc oxygen were introduced and closed the reaction mixture was irradiated at a temperature of 25 u00b0 30 u00b0 c in 2 5 3 hours by means of high pressure mercury lamp after removing oxide of nitrogen the resulting products were extracted with 20 cc dichloromethane but the crude solid remained in the tube which being taken out by means of insoluble liquid for example methanol and washed with dichloromethane this washed solution was incorporated with the extracted dichloromethane solution thus this incorporated solution was concentrated to a volume about 3 cc under a reduced pressure said concentrated dichloromethane solution was added to 0 5 cc liquid nitrogendioxide n 2 o 4 while the temperature of the reaction mixture was maintained between 18 u00b0 20 u00b0 c during the reaction after removing liquid n 2 o 4 the remained solid was washed with 20 cc dichloromethane which was incorporated with the solid obtained at the second step thus the total solid was purified the identification of adipic acid was made by its infrared spectrum ethylendichloride ethylendibromide chloroform bromoform and carbontetrachloride may be used as solvent the products in the photochemical reaction were extracted with dichloromethane and directly analyzed by gas chromatography this results and the quantity of obtained adipic acid are indicated in tables.