The Torsional Barriers of 2-Hydroxy- and 2-Fluorobiphenyl: Small but Measurable
By making use of a novel diastereotopicity probe, namely C(CF3)(2)OH, it has been possible to measure by very low temperature F-19 NMR spectroscopy the elusive aryl aryl rotation barriers of biphenyls bearing an OH or F group in one rill position. The experimental values (5.4 and 4.4 kcal mol(-1), respectively) are matched by those from ab initio calculations (5.3 and 4.3 kcal mol(-1), respectively).
Keywords: ab initio calculations ; biphenyls ; diastereotopicity probes ; NMR spectroscopy ; steric hindrance ; Dynamic Nmr ; Stereochemical Consequences ; Conformational-Analysis ; Absolute-Configuration ; Internal-Rotation ; Arylboronic Acids ; Carbon-Carbon ; Methyl-Ether ; Stereodynamics ; Atropisomers
Record created on 2011-12-16, modified on 2016-08-09