Confinement inside a Crystalline Sponge Induces Pyrrole To Form N-H⋅⋅⋅π Bonded Tetramers.

Chemistry

Key Laboratory of Pesticide & Chemical Biology of Ministry of Education, Hubei International Scientific and Technological Cooperation Base of Pesticide and Green Synthesis, College of Chemistry, Central China Normal University, Luoyu Road 152, 430079, Wuhan, P. R. China.

Published: July 2021

Based on the DFT-level-calculated molecular volume (V ) of pyrrole and its liquid density, pyrrole manifests the highest liquid density coefficient LD (defined as [V ×density ×0.6023]/FW) value of 0.7. Normal liquids have LD <0.63. This very high LD is due to the strong N-H⋅⋅⋅π interactions in solution, and hence pyrrole can be considered to be a pseudo-crystalline liquid. When trapped inside the confined space of a crystalline sponge, a reorientation of the N-H⋅⋅⋅π interaction is observed leading to specific cyclic N-H⋅⋅⋅π tetramers and N-H⋅⋅⋅π dimers, as verified by single-crystal X-ray crystallographic and computational methods. These tetramers are of the same size as four pyrrole molecules in the solid-state of pyrrole, yet the cyclic N-H⋅⋅⋅π intermolecular interactions are circularly oriented instead of being in the linear zigzag structure found in the X-ray structure of a solid pyrrole. The confinement thus acts as an external driving force for tetramer formation.

Download full-text PDF

Source
http://dx.doi.org/10.1002/chem.202100087DOI Listing

Publication Analysis

Top Keywords

liquid density
8
confinement inside
4
inside crystalline
4
crystalline sponge
4
sponge induces
4
induces pyrrole
4
pyrrole form
4
form n-h⋅⋅⋅π
4
n-h⋅⋅⋅π bonded
4
bonded tetramers
4

Similar Publications

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!