Crystal and molecular structure of tetracarbonyl-(7,7-dimethoxynorborn-2-ene)chromium(0)

Abstract

The crystal and molecular structure of the title compound has been determined from diffractometer data (840 reflections) and refined by full-matrix least-squares to R 0·047. Crystals are orthorhombic, space group P2₁2₁2₁, a= 14·786(2), b= 10·137(1), c= 9·440(1)Å, Z= 4.

The chromium atom is octahedrally co-ordinated by the organic ligand which is bidentate through the olefinic bond and one of the methoxy-groups [Cr–C 2·248 and 2·300(8), Cr–O 2·152(5)Å] and by the four carbonyl groups. Among the latter, an interesting comparison is found between the opposed pair of carbonyl groups with Cr–C 1·915 ± 0·015 and C–O 1·125 ± 0·015 Å and the pair opposite the ligand with Cr–C 1·83 ± 0·015 and C–O 1·165 ± 0·015 Å.