XIV.—Contributions from the Laboratory of the University of Zurich. II. Piazine-derivatives

Arthur T. Mason
1889 Journal of the Chemical Society Transactions  
IN a paper pnblkhed in the Berichte (20, 267), entitled "Ueber Condensations-derivate des Aethylendiamins," I described, amongst others, two substances belonging to a class of nitrogenous compounds to which, at the suggestion of Professor Merz, I gave the name " pyrazines ; " this has since been changed t o " piazines."" The * I n a paper which has just appeared in t,he Journal fiir pmktische Chemie (38, 185)) Professor Widman discusses the defective nomenclature at present adopted in the
more » ... dopted in the aromatic, and more especially in the alkalo'id series. I n many caws, the names have been chosen so as to indicate as far a~ possible the methods of preparation first discovered, and then subsequent investigators, seeing the inappropriateness of the terms thus given, have adopted new ones, so that in not a few cases we have one and the same compound referred to by different investigators under totally different names. A good illustration of this is offered in the many changes which the important nitrogenous compound, above mentioned under the name of " piazine," hm undergone. Its tetramethyl-derivative was discovered in 1879 by G utknecht in V. Meyer's laboratory (Ber., 12, 2290), and several other derivatives were immediutely afterwards studied by Treadwell and by Treadwell and Steiger (Ber., 14, 1461 ; 15, 1059), and named a t the suggestion of Victor Meyer " ketines." At the suggestion of Professor Merz I afterwards proposed the name " pyrazines" (Ber., 20, 267), and in the same Journal, Wolff adopted independently the same terni (Ber., 20,425) in both instances, with the object of bringing out the analogy with the " pyridines." Victor Meyer, finding the term " ketines ') inappropriate afterwards, and objecting to " pyrazines )' on the ground that Knorr (Annalen, 238, 144) had already used that term for pyrazole tetrahydride, now proposed " aldines " (Ber., 21, 20), but most of the investigators who have worked on this group still adopt the name " pyrazines." This single instance shows that a state of chaos exists, and that some systematic nomenclature is an abRolute necessity. I n accordance with this, Widman has propounded a systematic nomenclature for all compounds containing nitrogen in the ring. Every compound is an "azine" which contains a ring consisting of six atoms of carbon and nitrogen. He calls them respectively monuzines, diazines, triazines, &c., according as they contain one or more atoms of nitrogen. To the "monazines" we should strictly have to reckon pyridine and quinoline, but to alter existing names in these cases is impracticable and unnecessary. The I' diazines " are divided into three great classes, according as they contain the nitrogen-atoms in para-, meta-, or orthoposition relatively to each other. The first member of the para-class would thus be styled " paradiazine," but as this is rather long, " piazine " can be used. In the meta-class we should have " metadiazine," which when shortened gives
doi:10.1039/ct8895500097 fatcat:flivj2a7uveovhppusm5yb4pqq