Pyrazinedioxide–Tetracyanoethylene Arrays in the Solid State—New Donor–Acceptor Interaction for Crystal Engineering


  • This research was supported by the United States National Science Foundation (NSF projects CHE-9200144 and CHE-9626144) and by the University of Alabama. We thank L. M. Rogers for assistance with X-ray crystal structures. B. J. M. was supported by the NSF REU program (CHE-9531496).


original image

Ladder and web polymorphic forms of cocrystals of tetramethylpyrazinedioxide (TMPDO) and tetracyanoethylene (TCNE) are obtained by rapid or slow crystallization, respectively. In the thermodynamically less stable, purple (TMPDO)2− TCNE crystals the donor and acceptor building blocks are linked through N+O°C(alkene) interactions to form one-dimensional ladders (see picture below).