Viability of aromatic all-pnictogen anions
Subhajit Mandal1, Surajit Nandi2, Anakuthil Anoop2
1Department of Chemistry and Centre for Theoretical Studies, Indian Institute of Technology Kharagpur, Kharagpur 721302, India. pkc@chem.iitkgp.ernet.in and Department of Chemistry, Indian Institute of Technology Kharagpur, Kharagpur 721302, India. anoop@chem.iitkgp.ernet.in.
Physical Chemistry Chemical Physics : PCCP
|January 9, 2016
Summary
Novel cyclic all-pnictogen anions, P2N3(-) and P3N2(-), exhibit aromaticity similar to cyclopentadienyl anion. Computational studies confirm their stability and potential as ligands in organometallic chemistry.
Area of Science:
- Inorganic Chemistry
- Theoretical Chemistry
- Computational Chemistry
Background:
- Aromaticity is a key concept in chemistry, influencing molecular stability and reactivity.
- Cyclic all-pnictogen heterocyclic anions represent a novel class of compounds with unexplored electronic properties.
Purpose of the Study:
- To investigate the aromaticity of P2N3(-) and P3N2(-) anions and their heavier analogues.
- To explore the stability and potential applications of these novel pnictogen heterocycles.
Main Methods:
- Quantum mechanical computations were employed to optimize geometries and analyze electronic structures.
- Quantum Theory of Atoms in Molecules (QTAIM) was used for electron density analysis.
- Nucleus-independent chemical shift (NICS) and ring current density plots were calculated to assess aromaticity.
Main Results:
- Geometrical parameters, bonding analysis, NICS, and ring current density plots strongly support the aromatic nature of P2N3(-) and P3N2(-).
- These anions exhibit aromaticity comparable to the prototypical cyclopentadienyl anion (C5H5(-)).
- The molecules are predicted to be stable up to 1000 fs and possess five distinct canonical structures.
Conclusions:
- P2N3(-) and P3N2(-) are confirmed as aromatic compounds with potential for synthetic accessibility via a click reaction.
- The study suggests P3N2(-) can act as a η(5)-ligand in metallocenes, with bonding characteristics elucidated by energy decomposition analysis.
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