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Updated: Apr 30, 2026

Accessing Valuable Ligand Supports for Transition Metals: A Modified, Intermediate Scale Preparation of 1,2,3,4,5-Pentamethylcyclopentadiene
Published on: March 20, 2017
Exploring cyclopentadienone antiaromaticity: charge density studies of various tetracyclones
Rumpa Pal1, Somnath Mukherjee, S Chandrasekhar
1Solid State and Structural Chemistry Unit and ‡Organic Chemistry, Indian Institute of Science , Bangalore-560012, India.
Abstract:
A systematic study of six tetracyclones has been carried out using experimental and theoretical charge density analysis. A three pronged approach based on quantum theory of atoms in molecules (QTAIM), nucleus independent chemical shifts (NICS) criterion, and source function (SF) contributions has been performed to establish the degree of antiaromaticity of the central five-membered ring in all the derivatives. Electrostatic potentials mapped on the isodensity surface show that electron withdrawing substituents turn both C and O atoms of the carbonyl group more electropositive while retaining the direction of polarity.
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