1,1,2,2-Tetracyanocyclopropane (TCCP) as supramolecular synthon

Area of Science:

• Supramolecular Chemistry
• Computational Chemistry
• Organic Synthesis

Background:

• The 1,1,2,2-tetracyanocyclopropane (TCCP) unit is a synthetically accessible building block.
• TCCP can engage in interactions via its lone-pair or π-electrons, termed 'non-covalent carbon bonding'.

Purpose of the Study:

• To computationally investigate the binding affinities of TCCP with diverse molecular entities.
• To explore the potential of TCCP as a novel supramolecular synthon.

Main Methods:

• Density Functional Theory (DFT) calculations using the BP86-D3/def2-TZVP level of theory.
• Computation of binding energies for TCCP complexes with various guests.

Main Results:

• TCCP forms stable complexes with neutral molecules (e.g., aromatics, amino acids) and anionic species.
• Binding energies range from -10 kcal mol⁻¹ for neutral guests to -15 to -50 kcal mol⁻¹ for anionic species.
• These binding strengths are comparable to strong and very strong hydrogen bonds.

Conclusions:

• TCCP represents a new class of supramolecular synthons.
• The computational findings suggest TCCP has significant potential for experimental supramolecular chemistry applications.
• TCCP offers an alternative to traditional synthons based on polarized hydrogen or halogen atoms.