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.
Paal has also obtained pyrrol derivatives by condensing acetophenone-acetoacetic-ester with substances of the type NH2R.
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.
It combines with acetoacetic ester to form the aromatic compound meta-oxyuvitic acid, C 6 11 2 CH 3 OH (Cooh) 2.
CH 3 CO CHX CO 2 C 2 H 5, derivatives of acetoacetic ester.
Acetoacetic ester is a most important synthetic reagent, having been used in the production of pyridines, quinolines, pyrazolones, furfurane, pyrrols, uric acid, and many complex acids and ketones.
In this reaction the proportions of aldehyde and acetoacetic ester may be interchanged and ay disubstituted pyridines are then obtained.
At iio° C. aniline and acetoacetic ester condense to form anilido-acetoacetic ester, CH 3 C0 CH 2 C0 NH C 6 H 51 which is converted by concentrated acids into a-oxy-y-methylquinoline (L.
CO 2 H,with sodium amalgam, by conversion of trimethylene bromide into the cyanide and hydrolysis of this compound, or from acetoacetic ester, which, in the form of its sodium derivative, condenses with j3-iodopropionic ester to form acetoglutaric ester, CH 3 CO CH(CO 2 C 2 H 5) CH 2.