The crystal and molecular structure of 1,3‐diazanaphthalene

X-ray diffraction data of 1,3-diazanaphthalene or quinazoline have been collected at room temperature, using a computer-controlled Philips diffractometer (PW 1100). The unit cell is triclinic, P i (assumed), two molecules in the asymmetric unit, with a= 11.983 (1), b=7.8555 (5), e=7-4660 (5) A~, a=91.13 (1), fl=99.84 (1), y=108.73 (1) °, Z=4. The structure was solved by direct methods and refined in two blocks by the full-matrix least-squares method to an R index of 0.046 (weighted R 0-042). Within experimental error, both molecules in the asymmetric unit can be considered identical in shape, with small (~0.01 .~), but significant, deviations from planarity. The crystals invariably showed twinning. The orientations of the components of the twin differ by a rotation of 180 ° around the [211] direct axis.