The preparation of triazines and benzimidazoles from 1‐ and 3‐cyanoisoquinolines

Abstract

The preparation from 1‐ and 3‐cyanoisoquinolines of certain benzimidazoles and symmetrical triazines containing the ferroin group is described; also that of certain unsymmetrical triazines from 3‐cyanoisoquinoline.

Synthesis, crystal structures, electrochemical and spectroscopic properties of ruthenium(II) complexes containing diamino-1,3,5-triazine derivatives

“…[16] with some modification. A mixture of isoquinoline-1-carbonitrile (3.08 g, 20 mmol), dicyandiamide (1.53 g, 18.2 mmol), potassium hydroxide (0.21 g, 3.6 mmol) and 2-methoxyethanol (10 cm 3 ) was refluxed for 4 h. The reaction mixture was then cooled to room temperature.…”

“…The ligands were synthesized on the basis of the method established by Case [16]. This method provides a very convenient way to prepare various 2,4-diaminotriazines.…”

Chemistry of amidrazones

“…The use of thioimidates56 has received less attention but an aminoguanidinium iodide (32) was obtained by warming hydrazine hydrate with the corresponding isothiourea,57 and When 2 moles of hydrazine to 1 mole of imidate salt was employed, a dihydroformazan (30) On the other hand, a dihydrotetrazine (26, R = 4-pyridyl) and a 4-amino-l ,2,4-triazole (29, R = 4-pyridyl) resulted from the interaction of benzyl pyridine-4-thioimidate and hydrazine hydrate in alcohol. 27 In this connection it has been reported that the Pinner procedure can be modified to give good yields of s-tetrazines (27), via their dihydro derivatives (26), in place of amidrazones by working in anhydrous conditions and using methanolic triethylamine in place of aqueous base.69,60 It does appear, however, that the nature of the grouping, R of the imidate or thioimidate (35), also plays at least some part in determining the form of the final product.61 Other compounds prepared via thio- Thioimidate salts have also been used successfully in the synthesis of some heterocyclic amidrazones,78 diamidrazones,78 and compounds in which the amidrazone grouping forms part of a heterocyclic ring system74 (40).…”