ON THE: NATURE gravity at 15/15, 0.7954, optical rotation, -0.7', and refractive index a t Z O O , 1.4705. These figures are close to those recorded for myrcene.This fraction boils at 164-166' at atmospheric pressure with partial polymerization.Oxidation with permanganate gave succinic acid, m. p.186 ' . Reduction with sodium in alcohol yielded dihydromyrcene (tetrabromide m. p. 89-90"), and hydration with acetic acid and 50% sulfuric acid a t low temperature gave myrcenol, having a lavender odor and giving a phenylurethan melting at 71-72'.(Enklaarz reported a melting point of 68" for myrcenol phenylurethan.) The phenylurethan from the myrcenol gave sharp depressions in melting point when mixed with both I-linalool and i-linalool phenylurethans.The small higher boiling fraction remaining after distillation of the myrcene was redistilled a t 10 mm. from a small flask provided with a Vigreux column yielding the following products: (1) a very small fraction, 85-90";(2) a small fraction, 90-100°; (3) the main fraction, 100-110"; (4) a small fraction, 110-140"; leaving a thick, viscous residue in the flask.Fraction 1 gave a negative reaction for alcohols on treatment with phenyl isocyanate, but gave a positive reaction for the carbonyl group on treatment with semicarbazide, as did also fractions 2 and 3, which gave copious yields of semicarbazone. On decomposition of the semicarbazones an odor suggesting methyl nonyl ketone was observed.The semicarbazone from fraction 1 melted a t 114.5". The semicarbazones from fractions 2 and 3 melted at 123-124 ' , and gave no depression in melting point when mixed with the semicarbazone of methyl It-nonyl ketone. While (2) Enklaar, "Over Ocimeen en hlyrceen," Inaugural Dissertation, Utrecht, 1905 OF PYROABIET~C ACIDS 92 1 indices of refraction were not measurable in either case, optical crystallographic examination showed identical crystalline form and interference figures.'Fraction 3, boiling a t 10C)-llOo, had an odor suggesting geraniol. When a portion of this fraction was oxidized with potassium dichromate, an odor of citral was detected. However, attempts to isolate geraniol as the diphenylurethan, or the semicarbazone of citral, were unsuccessful, due no doubt to the predominance of methyl It-nonyl ketone.From the distillation residue a non-volatile oil was extracted which gives a lasting tingling sensation to the tongue and lips. Alkaloidal material was found only in traces, so this physiological effect is not due to aconitine. This substance is being further investigated.
SummaryThe volatile oil of Amur cork tree fruit coiitains over 92% of the aliphatic terpene, myrcene.The higher boiling portion of the oil contains methyl n-nonyl ketone, with possibly a small amount of a lower homolog such as methyl nheptyl ketone.Evidence was obtained of the presence of a small amount of geraniol in the fraction boiling at 100-llOo at 10 mm.The slight optical activity of the myrcene fraction is probably due to a small amount of an optically active terpene.(3) Optical crystallographic e...
