Crystal and Molecular Structures of Tetraisopropyl 1,1′-(1,8-Naphthylene)bis[1H-1,2,3-triazole-4,5-dicarboxylate] and Diisopropyl 1-(1-Naphthyl)-1H-1,2,3-triazole-4,5-dicarboxylate

Molecular structures of the title compounds, which belong to the class of peri-substituted naphthalenes, have been determined by means of X-ray diffraction. Tetraisopropyl 1,1′-(1,8-naphthylene)bis[1H-1,2,3-triazole-4,5-dicarboxylate] (1), monoclinic, space group C2⁄c, a=35.034(3), b=9.717(1), c=18.504(1) Å, β=96.43(1)°, Z=8; Diisopropyl 1-(1-naphthyl)-1H-1,2,3-triazole-4,5-dicarboxylate (2), monoclinic, space group P21⁄n, a=16.246(2), b=10.115(1), c=12.390(1) Å, β=96.67(1)°, Z=4. The dihedral angles between the mean plane of the naphthalene ring and that of the triazole ring are 88° and 85° for 1 and 2, respectively. The naphthalene framework of 1 is much more distorted than that of 2 because of a steric repulsion between the two triazole rings with bulky ester groups of 1.