Crystal and molecular structure of benzonorbornen-anti-9-yl p-bromobenzenesulphonate

Abstract

The crystal structure of benzonorbornen-anti-9-yl p-bromobenzenesulphonate, C₁₇H₁₅BrO₃S, has been determined by a three-dimensional X-ray analysis. The crystals are monoclinic, a= 23·453, b= 8·977, c= 16·338 Å, β= 112° 38′, Z= 8, space group C2/c. The intensities were measured with a Hilger and Watts automatic four-circle diffractometer using Mo-K_α radiation. The structure was solved by the programme SEARCH, for the automatic heavy-atom analysis, and refined by full-matrix least-squares calculations to a final R of 0·060 for 1813 independent observed reflexions. The bond distances in the molecule are all as expected, but the valency angles suggested the presence of considerable steric strains within the benzonorbornene nucleus. The bridgehead angle is 96°, not significantly different from the corresponding angle in the syn-9-benzonorbornene nucleus.