The crystal structure of 5-hydro- and 7-hydro-s-indacenide-Rh(COD). A comparison with similar complexes

The monometallic complex with Rh(COD) of 5-hydro and 7-hydro-s-indacenide has been synthesized and structurally characterized. It crystallizes in the triclinic space group with a=12.513(2), b=15.902(2), c=8.423(1) Å, α=97.0(1), β=91.4(1), γ=111.7(1)°. The geometry of the ligand was revealed to be substantially different from that of its 2,6-dimethylated homologues. An explanation for this behaviour is given in terms of electronic and mesomeric effects.