Experimental and theoretical study of intramolecular O⋯O interaction in structurally rigid β-keto carboxylic esters. Issue 94 (26th September 2016)

• Record Type: Journal Article
• Authors: Sharma, Chiranjeev; Singh, Ashawani K.; Joy, Jyothish; Jemmis, Eluvathingal D.; Awasthi, Satish K.
• Is Part Of: RSC advances. Volume 6:Issue 94(2016)
• Page Start: 91689
• Page End: 91693
• Publication Date: 2016-09-26
• Subjects: Chemistry -- Periodicals; 540.5
• DOI: 10.1039/c6ra20483j
• Languages: English
• ISSNs: 2046-2069

Abstract

Abstract : Herein, we present our experimental and theoretical study on the crystal structures of quinolone carboxylate and bisethoxycarbonylvinylanilines, which gives an insight into the origin of the attractive or repulsive nature of O⋯O interactions. Abstract : Here we report the crystal structures of quinolone carboxylate and bisethoxycarbonylvinylaniline derivates containing an O⋯O distance shorter than the sum of their van der Waals radii, which can be ascribed to their steric demand per se, which provide unequivocal evidence of intramolecular 1, 5-closed shell type interaction. Theoretical studies including Quantum Theory of Atoms in Molecules (QTAIM) and Natural Bond Orbital (NBO) analysis are employed to characterize the nature of the closed shell O⋯O interaction. We found that the lone pair electrons on the interacting oxygens undergo stabilization due to negative hyperconjugation and maintains the otherwise repulsive O⋯O close contact.