Self-assembly of conducting cocrystals via iodine⋯π(Cp) interactions

Abstract

Conducting crystals of alternating ferrocene and diiodoacetylene units assembled into supramolecular 1-D chains via I⋯π(Cp) halogen bonds were prepared and structurally characterized.

Disubstituted Ferrocenyl Iodo- and Chalcogenoalkynes as Chiral Halogen and Chalcogen Bond Donors

“…In all obtained crystal structures, I···C XBs are observed between the electropositive σ-hole of the iodine atom and electron-rich π clouds (Tables S3–S10 and Table S11). Interestingly, the XB acceptors vary and can be the alkyne carbon atoms (( S Fc )- 12a , ( R Fc )- 13 , ( S Fc )- 9a ), the cyclopentadienyl rings bearing the alkyne group ( 13 , ( S Fc )- 11a , ( S Fc )- 11b ), the unsubstituted cyclopentadienyl rings ( 9c , ( S Fc )- 9c ), or the naphthyl group ( 11b ). The negatively charged belts usually found around polarized heavy halogen atoms (see the Supporting Information) are not involved as σ-hole acceptors in these structures; thus, no halogen···halogen bonds are evidenced for these compounds.…”

Metal Centers as Nucleophiles: Oxymoron of Halogen Bond‐Involving Crystal Engineering

“…Commonly used HaB acceptors (electron donors) are lone pair (LP)-bearing atoms, such as halogens and lighter chalcogens and pnictogens. Furthermore, electron-rich C atoms (for example, in carbenes R 2 C:, [36] isocyanides RNC:, [37] carbon monoxide OC:, [38] and anionic species such as alkyl carbanions C(sp 3 ) À [39] ) and π-systems (for example, À C=CÀ , À C�CÀ , arene) [40][41][42] have also been recognized as good HaB acceptors.…”

High-Pressure Behavior of C2I2 and Polymerization to a Conductive Polymer

“…36,37 Other studies have used diiodoacetylene to synthesize conductive polymers through cocrystallization methods and radiation polymerization techniques. 38,39 Up until now, no reports have been made regarding the high-pressure behavior of the dihaloacetylenes. As evidenced by their extreme reactivity, it is expected that they will undergo polymerization chemistries at pressures low enough to be suitable for scalability (typically < 10 GPa).…”

“…For some time, the structural chemistry of the dihaloacetylenes was debated with some investigators favoring an acetylidene structure (X 2 CC) with a bivalent carbon atom, whereas others favored a linear molecule. , Vibrational spectroscopic investigations of the dihaloacetylenes resulted in support for a linear geometry. − As diiodoacetylene is a solid at ambient conditions, the crystal structure was determined by single-crystal X-ray diffraction (XRD), providing further evidence of linear geometry . Attempts to polymerize diiodoacetylene to carbyne by a number of methods produced polymeric carbon materials that exhibited features of a polyyne material. , Other studies have used diiodoacetylene to synthesize conductive polymers through cocrystallization methods and radiation polymerization techniques. , …”