File:Image from page 260 of "Practical methods of organic chemistry" (1901) (14771317932).jpg

Identifier: practicalmethods00gatt Title: Practical methods of organic chemistry Year: 1901 (1900s) Authors: Gattemann, Ludwig. [from old catalog] Subjects: Publisher: [n.p.] Contributing Library: The Library of Congress Digitizing Sponsor: The Library of Congress

View Book Page: Book Viewer About This Book: Catalog Entry View All Images: All Images From Book

Click here to view book online to see this illustration in context in a browseable online version of this book.

Text Appearing Before Image: stirring and good cooling,25 grammes of potassium dichromate, powdered extremely fine.On the next day add 50 grammes of this salt. In other respects,proceed as above. Many primary aromatic amines yield quinones on oxidation withchromic acid. But the reaction cannot be expressed in a simple equa-tion ; still, it is always true that the amido-group and the hydrogen AROMATIC SERIES 241 atom in the para position to this are each replaced by an oxygenatom, e.g.: CCH5. NH2 —■>- C6H402 Quinone o-C6H4- C0H3/ \NH2 ^02 Toluidine Tolyl quinone The tendency to form quinones is so great that even in cases where thepara position to the amido-group is occupied by an alkyl (methyl) radical,the latter is split off and a quinone (poorer in carbon contents) is formed.Indeed, in the simplest cases, like p-toluidine and asym. m-xylidine, thereaction is very incomplete; however, mesidine, as well as pseudocumidine,give satisfactory yields of quinones belonging to the next lower series: NH9

Text Appearing After Image: '

Note About Images