Origin and Production. In the London market the fruits of Xanthoxylum alatum, Roxb., are offered under the name of "Chinese wild pepper". The shrub which belongs to the family Rutaceae occurs in northern Bengal, also in China.
1) Report of Schimmel & Co. April 1901, 59.
Upon distillation of these fruits Schimmel & Co.1), obtained 3,7 p. c. of oil which has a lemon yellow color and a peculiar odor reminding of water fennel. Upon continued distillation an additional 0,9 p. c. of a crystalline substance were obtained. The attempt to dissolve these crystals, in the proportion recorded above, in the oil had to be abandoned since the bulk thereof crystallized out again at a temperature between 25 and 30°. Hence the properties of oil and solid substance were determined separately.
The oil revealed the following properties: d15o0,8653; aD - 23°35'; nD20o1,48131; A. V. 0,9; E. V. 10,3; E. V. after acet-ylation 33,6; soluble in 2,6 vol. or more of 90 p. c. alcohol. After several recrystallizations from alcohol, the solid substance was obtained in colorless and odorless needles or in laminae which melted at 83° and which were optically inactive. They are extremely soluble in ether, chloroform and acetone, less so in benzene, alcohol and petroleum ether.
For one distillate Umney2) determined d 0,889; aD - 23°.
Composition. In the oil F. W. Semmler and E. Schossberger3) found a terpene (b. p. 50 to 60° at 9 mm.; d20o,0,840; aD - 26°; nD 1,47457), which they named xanthoxylene, but which may prove identical with l-sabinene. It yields a monochlorhydrate (b. p. 83 to 87° under 10 mm. pressure; d20o 0,959; aD - 11°; nD 1,4824), which, upon reduction with sodium and alcohol, yields a hydrocarbon C10H18 with the following properties: b. p. 52 to 58° (9 mm.); d20o 0,8275; aD - 17°; nD 1,4582. When ozonized xanthoxylene yields a ketone, the semicarbazone of which melts at 123°, whereas sabinene ketone semicarbazone melts at 141°.
According to Semmler and Schossberger, the solid constituent mentioned above is the dimethyl ether of phloraceto-phenone4), C10H12O4, the monobromo derivative, C10H11BrO4, of which melts at 187°, the acetyl derivative at 107° and the methyl derivative at 103°.
1) Report of Schimmel & Co. October 1910, 147. 2) Perfum. and Essent. Oil Record 3 (1912), 37. 3) Berl. Berichte 44 (1911), 2885.
4) The same substance had previously been found in the oil of Blumea balsamifera. Report of Schimmel & Co. April 1909, 150.
As further constituent of the oil an aldehyde was separated, the semicarbazone of which melted at 210 to 211°. Hence it may be regarded as cuminic aldehyde1).
J. Stenhouse2) investigated an oil supposed to have been derived from Xanthoxylum piperitum, DC. As determined later by Hanbury, it was derived from X. alatum. Stenhouse had found a terpene which boiled at 162° and which he named xanthoxy-lene, and a crystalline substance, C10H12O4, which melted at 80° and which he named xanthoxyjin. Both observations agree well with the later ones of Semmler and Schossberger.