Di:amino-pyrazolo-pyrazole-di:one - useful as intermediate, esp. for dyes, pharmaceuticals and plant protection agents

摘要

1,2-a pyrazole-3, 7-dione of formula (I) and its alkali(ne earth) metal salts and acid-addn. salts are new: (I) is prepd. by cyclising N,N'-bis(cyanoacetyl)hydrazine of formula (NCCH2CONH)2 (II) in the presence of an acid or base, opt. in solvent or diluent, at a temp between - 20 degrees C and the b.pt. of the reaction mixt. (I) is useful as an intermediate for dyes (esp. mono-and disazo dyes), pharmaceuticals and plant protection agents.