Held synthesized the acid from ethyl chlor-acetoacetate (from chlorine and acetoacetic ester) by heating with potassium cyanide and saponifying the resulting nitrile.
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.
We may here mention the synthesis of oxyuvitic ester (5-methyl-4-oxy-I-3-benzene dicarboxylic ester) by the condensation of two molecules of sodium acetoacetic ester with one of chloroform (Ann., 1883, 222, p. 249).
He also found that diaceto succinic ester reacts with compounds of the type NH 2 R(R = H, CH 3, OH, NHC 6 H 5, &c.) to form pyrrol derivatives CH3 CO CH CO 2 R, C(CH3) :C C02R A NH 2 R -?- - RN(CH 3 CO CH CO 2 R C(CH3) :C C02R By using compounds of the type NH 2 R and acetophenone acetoacetic ester C 6 H 5 CO CH 2.
ANTIPYRINE (phenyldimethyl pyrazolone) (C11H12N20), is prepared by the condensation of phenylhydrazine with acetoacetic ester, the resulting phenyl methyl pyrazolone being heated with methyl iodide and methyl alcohol to loo-110° C.: CH 0=N CH3 C-N CH3 >N C6H5 - II >N C6H6 CH 2 -CO HC-CO Phenyl methyl pyrazolone Antipyrine On the large scale phenylhydrazine is dissolved in dilute sulphuric acid, the solution warmed to about 40° C. and the aceto-acetic ester added.