Poplar Buds(CHAPTER V. The Flavone Group.)(Osa artikkelista)

The Natural Organic Colouring Matters
By
Arthur George Perkin, F.R.S., F.R.S.E., F.I.C., professor of colour chemistry and dyeing in the University of Leeds
and
Arthur Ernest Everest, D.Sc., Ph.D., F.I.C., of the Wilton Research Laboratories; Late head of the Department of Coal-tar Colour Chemistry; Technical College, Huddersfield
Longmans, Green and Co.
39 Paternoster Row, London
Fourth Avenue & 30th Street, New York
Bombay, Calcutta, and Madras
1918

Kaikki kuvat (kemialliset kaavat) puuttuvat // None of the illustrations (of chemical formulas) included.

Chrysin, C₁₅H₁₀O₄, is contained in the leaf buds of the poplar (Populus pyramidalis, Salisb., P. nigra, Linn., P. monilifera, Ait.), in which it is present to the extent of about ¼ per cent. It was first isolated by Piccard (Ber., 6, 884, 1160; 7, 888; 10, 176) and is best prepared by the method devised by this chemist.

An alcoholic extract of 1000 grams of poplar buds is treated while hot with about 120 grams of lead acetate, and after standing for some time the yellow precipitate is removed. Through the clear filtrate sulphuretted hydrogen is passed in order to decompose lead salts, the sulphide of lead is filtered off and the liquid evaporated to dryness. The residue dissolved in a little hot alcohol gradually deposits crystals ofchrysin, which are collected, successively extracted with carbon disulphide, benzene, and boiling water, and finally crystallised two or three times from alcohol.

[---]

Chrysin is a feeble dyestuff. The shades produced on wool mordanted with aluminium, chromium, and iron, are respectively pale bright yellow, pale yellow-orange, and chocolate-brown.

Tectochrysin, a second constituent of poplar buds, is present in the benzene extracts from the crude chrysin. Tectochrysin is chrysin monomethylether, (C₁₅H₉O₃.OCH₃), (Piccard), and is identical with the methylation product of chrysin itself (loc. cit.).