Substituent effects on the reduction of 2-alkylcyclohexanones by LiAlH4: an investigation of conformational equilibria and transition states

Author(s)

Bocca, Cleverson C. ^[1] ; Rittner, Roberto ^[1] ; da Silva, Alan P. ^[2] ; Basso, Ernani A. ^[2]

Affiliation

^[1] Univ Estadual Campinas, Inst Chem, Campinas, SP - Brazil

^[2] Univ Estadual Maringa, Dept Chem, BR-87020900 Maringa, Parana - Brazil

• Document type: Journal article
• Source: JOURNAL OF PHYSICAL ORGANIC CHEMISTRY; v. 24, n. 3, p. 241-248, MAR 2011.
• Web of Science Citations: 3

Abstract

Transition state (TS) structures for the reduction of 2-Me and 2-i-Pr-cyclohexanone by LiAlH(4) were optimized by density functional theory (B3LYP/6-31G(d,p)). Four TS structures corresponding to axial and equatorial attacks by LiAlH(4) were located for each ketone conformer. Electronic potential maps were used to investigate the substituent electronic effect on the IS stabilization. The uneven carbonyl orbital distribution in the LUMO (pi{*}) was also analyzed. Reduction stereoselectivity was shown to depend on both the ketone conformational ratio and on the reaction TS. Copyright (C) 2010 John Wiley \& Sons, Ltd. (AU)

• FAPESP's process: 05/59649-0 - Conformational equilibria studies by nuclear magnetic resonance spectroscopy, infrared spectroscopy and theoretical calculations
• Grantee: Roberto Rittner Neto
• Support Opportunities: Research Projects - Thematic Grants