Phenyl Ring Orientations in Two Tetracyclone Adducts; X-Ray Crystal Structures of exo-and endo-1,7,8,9-Tetraphenyltricyclo-[5.2.1.0^2,6]deca-3,8-dien-10-ones

Abstract

The crystal structures of exo- and endo- 1,7,8,9- tetraphenyltricyclo [5.2.1.0^2,6]deca-3,8-dien-10-one (8) and (9) are reported. Crystals of the exo adduct (8) are triclinic: Pī , a 9.863(2), b 10.738(2), c 13.634(2) Ǻ, α 82.90(1), β 68.87(1), γ 66.87(1)°, Z 2; crystals of the endo adduct (9) are monoclinic: P2₁/c, a 11.610(1), b 7.862(2), c 27.675(3) Ǻ, β 100.223(9)°, Z 4. The structures were refined to R 0.039 and 0.049 respectively. The relative orientations of the four phenyl rings in the two structures are similar.