1594 LEES : METEYL P-METHYLHEXYL KETONE. C L I X . --Met J?yl ,&Net JL y I hex y I Ketone. By FREDERIC HERBERT LEES. IN the course of an investigation of the ketones contained in an essential oil of rue (this vol., p. 1585), methyl P-methylhexyl ketone, CH,-CO*CH2*CH(CH3)*[CH2]3*GH3, mas prepared and characterised. It was obtained by the hydrolysis of ethyl see,-hexylacetoacetate, CH,*CO*CH(C,H,,)*CO,Et, which was prepared by the condensa- tion of see.-hexyl iodide (from mannitol) with ethyl acetoacetate. Ethyl sec. -hexyZacetoacetate.-Sodium (5.8 grams) was dissolved in absolute alcohol (60 c.c.), and to the solution mere successively adde'h, ethyl acetoacetate (3'2.5 grams), and sec.-hexyl iodide (53 grams). TheLEES : METHYL P-METHYLHEXYL KETONE. 1595 resulting clear liquid was then heated in a soda-watef bottle at 100' for 14 hours, when the product became neutral.The greater part of the alcohol was removed by distillation, water was then added, and the precipitated oil taken up with ether. The ethereal solution was washed with water, dried with calcium chloride, and the ether removed. The residue was then fractionally distilled under diminished pressure, when a quantity of the pure substance, amounting to 30 per cent. of that theoretically obtainable, distilled as a nearly colourless oil at 130-132' under 17 mm. pressure, Under the ordinary pressure, it boiled a t 243-245O. Its alcoholic solution gave a brown coloration with ferric chloride. On analysis : 0.131 gave 0.3198 CO, and 0.1 185 H,O. C,,H,,O, requires C = 67.3 ; H = 10.3 per cent.Methyl P-Methylhexyl Ketone.-Ethyl sec.-hexylacetoacetate (16 grams) was boiled with a solution of potassium hydroxide (10 grams) in water (20 c.c.) for nine hours. The oil was then dissolved in ether, the ethereal solution washed with water, dried with calcium chloride, and the ether removed, The residual oil was then fraction ated, when the ketone was obtained, to the extent of 80 per cent. of the theoretical, as a colourless, pleasantly odorous liquid, which boiled at 184O under 769 mm. pressure. A density determination gave d 15'/16O -0.8319. On analysis: C = 66.6 ; H = 10.1. 0.127 gave 0.3538 CO, and 0.1447 H,O. The semicarbazone, recrystallised from petroleum, formed rosettes of 0,1804 gave 0.4 CO, and 0.1728 H,O. C = 60.5 ; H= 10.6. The oxime, at the ordinary temperature, is a colourless oil. 0.1482 gave 0.3128 GO, and 0.1606 K,O. C = 68.6 ; H = 12.0. C = 76.0 ; H = 12.7. CgH,,O requires C = 76.1; H = 12.7 per cent. fine needles and melted a t 7 5 O . On analysis : C,,H,,ON, requires C = 60.3 ; H = 10.6 per cent. On analysis : CgH,,ON requires C = 68.8 ; H = 12.1 per cent. THE WELLCOME CHEMICAL RESEARCH LABORATORIES.