(Z)-4-(2,6-dichlorophenyldiazenyl)-6-{[1,3-dihydroxy-2-(hydroxymethyl)propan-2-ylamino]methylene}-2-methoxycyclohexa-2,4-dienone and the 3-methoxyphenyldiazenyl and 4-methoxyphenyldiazenyl analogues

Abstract

The title compounds, (Z)-4-(2,6-dichlorophenyldiazenyl)-6{[ 1,3-dihydroxy-2-(hydroxymethyl) propan-2-ylamino] methylene}2- methoxycyclohexa-2,4-dienone, C18H19Cl2N3O5, ( I), ( Z)-6-{[1,3- dihydroxy-2-(hydroxymethyl) propan-2-ylamino]methylene}- 2- methoxy-4-(3-methoxyphenyldiazenyl) cyclohexa-2,4- dienone, C19H23N3O6, (II), and ( Z)-6-{[ 1,3- dihydroxy-2-( hydroxymethyl) propan-2-ylamino] methylene}- 2-methoxy- 4-(4-methoxyphenyldiazenyl) cyclohexa-2,4- dienone, C19H23N3O6, (III), all adopt the keto - amine tautomeric form, and the hydroxy H atoms are located on the N atom in all three compounds. Strong intramolecular N - H center dot center dot center dot O hydrogen bonds arise as a result of the shifts achieved by the hydroxy H atoms of the Schiff bases to the N atoms. Positional disorder was observed in molecules ( II) and ( III). In all three compounds, C - H center dot center dot center dot pi and pi-pi interactions affect the packing of the molecules. The compounds exhibit trans geometry with respect to the azo N=N double bond, and the molecules are linked by O - H center dot center dot center dot O hydrogen bonds to form three-dimensional networks.