Solid state structure by X-ray and 13C CP/MAS NMR of new 5,5′-diethoxy-3,3′-methanediyl-bis-indole

5,5′-Diethoxy-3,3′-methanediyl-bis-indole 1 was synthesized by novel protocol and its solid state structure was analyzed using X-ray diffraction and 13C CP/MAS NMR methods. Double resonances were observed in the spectrum of 1, and different structure of both indole systems in one molecule (shown by X-ray studies) is responsible for this spectral pattern. In the crystal only one intermolecular hydrogen bond (N1–H1⋯O11′) was revealed, which is uncommon among bis-indole derivatives.