Perkin, junr., in 1883, that ethylene and trimethylene bromides are capable of acting in such a way on sodium acetoacetic ester as to form triand tetramethylene rings.
The transition between the two classes as differentiated above may be illustrated by the following cyclic compounds, each of which contains a ring composed of four carbon atoms and one oxygen atom: CH CH/ CH CH/ CH CO I CH CO' CH =CH c Tetramethylene But yrolactone.
It melts at 173° C.; and on reduction with sodium in alcoholic solution yields tetramethylene diamine.
Tetramethylene diamine (putrescine), NH 2 ï¿½ (CH2)4.
21-27, and 31), and are diphenyl tetramethylene dicarboxylic acids.
Soc., 1888, 53, p. 1 94): C2H4Br2+2NaCH(C02R)2--->(CH 2) 2 C(CO 2 R) 2 +CH 2 (CO 2 R) 2; ethyl butane tetracarboxylate is also formed which may be converted into a tetramethylene carboxylic ester by the action of bromine on its disodium derivative (W.
When sodio-malonic ester is condensed with trimethylene bromide the chief product is ethyl pentane tetracarboxylate, tetramethylene dicarboxylic ester being also formed, and from this the free acid may be obtained on hydrolysis.
Attempts to eliminate water from this acid and so produce an unsaturated acid were unsuccessful; on warming with sulphuric acid, carbon monoxide is eliminated and cyclo-butanone (keto-tetramethylene) is probably formed.