Aggregation Studies of Lithium Dialkylamides. The Role of Aggregates in the Carbonylation Reaction

Article abstract of DOI:10.1021/jo00059a042

13C NMR spectroscopy and isotopic exchange in carbonylation intermediates have been successfully employed to characterize aggregation of lithium dialkylamides in THF solution.It is shown that lithium (3-oxapentamethylene)amide forms a 1 : 1 mixed aggregate with morpholine.The aggregate remains even in diluted THF solution.Lithium pentamethyleneamide also forms aggregates with piperidine while the less acidic amines do not form mixed aggregates with the corresponding lithium dialkylamide either in the solid state or in THF solution.The product composition in the carbonylation reaction of lithium dialkylamides is highly dependent on their aggregation states, and this phenomenon can be successfully used for synthetic purposes.