Lithiated Imines:Solvent-Dependent Aggregate Structures and Mechanisms of Alkylation

摘要

We describe efforts to understand the structure and reactivity of lithiated cyclohexanone N-cyclohexylimine.The lithioimine affords complex solvent-dependent distributions of monomers,dimers,and trimers in a number of ethereal solvents.Careful selection of solvent provides exclusively monosolvated dimers.Rate studies on the C-alkylations reveal chronic mixtures of monomer-and dimer-based pathways.We explore the factors influencing reactants and alkylation transition structures and the marked differences between lithioimines and isostructural lithium dialkylamides with the aid of density functional theory calculations.