In 2022,Pisacic, Mateja; Kodrin, Ivan; Trninic, Amanda; Djakovic, Marijana published an article in Chemistry of Materials. The title of the article was 《Two-Dimensional Anisotropic Flexibility of Mechanically Responsive Crystalline Cadmium(II) Coordination Polymers》.Formula: C6H4N2 The author mentioned the following in the article:
Crystals of a family of six one-dimensional (1D) coordination polymers of cadmium(II) with cyanopyridines ([CdX2L2]n; X = Cl, Br, I; L = 3-cyanopyridine, 3-CNpy, 4-cyanopyridine, 4-CNpy) presented a variety of morphologies and mech. responses with dominant 2D-anisotropic flexibility, which has not been previously reported. All mech. adaptable crystals were 2D flexible and they displayed a variety of direction-dependent responses; in addition to 2D-isotropic flexibility observed for solely elastic materials, 2D-anisotropic flexibility was noticed for both elastic and elastic → plastic crystals. The consequences of fine and controlled structural variations on mech. behavior were addnl. explored via microfocus SCXRD and complementary theor. studies, revealing that the relative strength and direction of the hydrogen bonding interactions were the key parameters in delivering a specific mech. response. In the experiment, the researchers used many compounds, for example, 4-Cyanopyridine(cas: 100-48-1Formula: C6H4N2)
4-Cyanopyridine(cas: 100-48-1) belongs to pyridine. Pyridine is very deactivated towards electrophilic substitution with respect to benzene. For this reason classical formylation, using methods such as the Gattermann or Vilsmeier reactions, are not generally successful. Formula: C6H4N2