A COMBINED AB INITIO AND GAS ELECTRON DIFFRACTION STUDY OF THE MOLECULAR STRUCTURE OF 1,1-DICYANOCYCLOBUTANE

Article abstract of DOI:10.1016/0022-2860(87)85012-3

The molecular structure of 1,1-dicyanocyclobutane was investigated by gas electron diffraction and the results are compared with 4-21G ab initio gradient geometry refinements.In the cyclobutane ring C1-C2 > C2-C3 in contrast to structural trends generally observed for cyclobutyl systems with a single electronegative substituent.The C-C<*>N groups are slightly non-linear, with the C<*>N groups bent away from one another.The structural features observed can be rationalized in terms of a special electronic interaction between the geminal cyano groups, which is also suggested by the 13C NMR spectrum.