Conformations of 1,1-diethoxyethane: A matrix isolation infrared and ab initio study

✍ Scribed by V. Venkatesan; K.S. Viswanathan

• Publisher: Elsevier Science
• Year: 2011
• Tongue: English
• Weight: 673 KB
• Volume: 988
• Category: Article
• ISSN: 0022-2860
• DOI: 10.1016/j.molstruc.2010.11.078

✦ Synopsis

Conformations of 1,1-diethoxyethane (DEE) were studied using matrix isolation infrared spectroscopy. Infrared features of the lowest energy, G Ç G ± (tt) conformer and the first higher energy, TG À (tt) conformer of matrix-isolated DEE were observed for the first time. The experiments were supported by ab initio computations performed at the HF and B3LYP levels, using a 6-31++G ÃÃ basis set. The computed vibrational wavenumbers at the B3LYP/6-31++G ÃÃ level for the G Ç G ± (tt) and TG À (tt) conformers, were found to agree well with the experimentally observed features, leading to a definitive assignment of the infrared features of these conformers of DEE. At the B3LYP/6-31++G ÃÃ level, the energy of TG À (tt) conformer was found to be 0.42 kcal/mol above the ground state G Ç G ± (tt) conformer. AIM calculations were also performed to understand the role of intramolecular CAHÁ Á ÁO interaction in the conformational preferences in DEE.