7,7′,8,8′-Tetramethoxy-4,4′-dimethyl-3,5′-bichromene-2,2′-dione
نویسندگان
چکیده
In the title mol-ecule, C(24)H(22)O(8), the mean planes of the two coumarin units are inclined to each other at a dihedral angle of 79.93 (3)°. The attached meth-oxy groups form torsion angles of 7.65 (19) and 78.36 (14)° with respect to one coumarin unit, and angles of 9.01 (16) and 99.08 (11)° with respect to the other coumarin unit. In the crystal structure, weak inter-molecular C-H⋯O hydrogen bonds connect pairs of mol-ecules to form dimers, generating R(2) (2)(16) and R(2) (2)(18) rings; the dimers are linked by further weak inter-molecular C-H⋯O hydrogen bonds, forming extended chains. Additional stabil-ization is provided by weak C-H⋯π inter-actions.
منابع مشابه
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