A THEORETICAL STUDY OF MALONONITRILE ADDITION TO CARBONYL COMPOUNDS

摘要

The nucleophilic addition of the malononitrile anion (MN(-)) to formaldehyde was studied theoretically by the AM1 semiempirical MO method. The addition is found to be endothermic with a late productlike transition state on the reaction coordinate. Additions of MN(-) to a series of carbonyl compounds were studied in order to investigate the substituent effect on the energetics of the title addition and the nucleophilic attack reactivity. The solvent effect was stimulated by hydrogen bonding a single molecule of water to the formaldehyde oxygen and/or to the MN(-) anion. Its influence on the energetics and the transition-state geometry was estimated. The Hammond postulate was satisfied for the studied additions. (C) 1997 John Wiley & Sons, Inc. [References: 25]