Aromaticity of strongly bent benzene rings: persistence of a diatropic ring current and its shielding cone in [5]paracyclophane.

Phys Chem Chem Phys

Organic Chemistry & Catalysis, Debye Institute for Nanomaterials Science, Utrecht University, Utrecht, Netherlands.

Published: October 2011

Direct evaluation of the induced π current density in [5]paracyclophane (1) shows that, despite the significant non-planarity (α = 23.2°) enforced by the pentamethylene bridge, there is only a modest (ca. 17%) reduction in the π ring current, justifying the use of shielding-cone arguments for the assignment of (1)H NMR chemical shifts of 1 and the claim that the non-planar benzene ring in 1 retains its aromaticity (on the magnetic criterion).

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http://dx.doi.org/10.1039/c1cp21950bDOI Listing

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