Rapid Racemization in Thiazolidinediones: A Quantum Chemical Study†

Bharatam, Prasad V. ; Khanna, Smriti (2004) Rapid Racemization in Thiazolidinediones: A Quantum Chemical Study† The Journal of Physical Chemistry A, 108 (17). pp. 3784-3788. ISSN 1089-5639

Full text not available from this repository.

Official URL: http://doi.org/10.1021/jp0366522

Related URL: http://dx.doi.org/10.1021/jp0366522


Ab initio molecular orbital (MO) and density functional studies have been carried out on the keto−enol tautomerization process in thiazolidinediones to understand the mechanism of rapid racemization observed in these systems. MP2(full)/6-31+G* results on model thiazolidinedione 1 indicate that the energy difference between keto and enol tautomers is 24.04 kcal/mol, which is larger than that in acetaldehyde (16.23 kcal/mol). Neither the ring strain in 1 nor the electron delocalization in its tautomers is significant enough to facilitate rapid racemization through this mechanism. Reversible S-oxide formation increases the acidity of the hydrogen at the chiral center as well as provides an alternative path for tautomerization, suggesting that such a mechanism is responsible for the rapid racemization observed under physiological conditions.

Item Type:Article
Source:Copyright of this article belongs to American Chemical Society.
ID Code:116662
Deposited On:12 Apr 2021 11:36
Last Modified:12 Apr 2021 11:36

Repository Staff Only: item control page