Acetal Substitution Reactions: Stereoelectronic Effects, Conformational Analysis, Reactivity vs. Selectivity, and
Yuge Chun1, Khoi B Luu1, K A Woerpel1
1Department of Chemistry, New York University, 100 Washington Square East, New York, NY 10003 USA.
Abstract:
Acetal substitution reactions can proceed by a number of mechanisms, but oxocarbenium ion intermediates are involved in many of these reactions. Our research has focused on understanding the conformational preferences, structures, and reactions of these intermediates. This Account summarizes our observations that electrostatic effects play a significant role in defining the preferred conformations, and that torsional effects determine how those intermediates react. Neighboring-group effects are not as straightforward as they might seem, considering that oxocarbenium ion intermediates are in equilibrium with structures that involve stabilization by a nearby substituent.
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