A Rapid Injection NMR Study of the Reaction of Organolithium Reagents with Esters, Amides, and Ketones

作者：Plessel Kristin N; Jones Amanda C; Wherritt Daniel J; Maksymowicz Rebecca M; Poweleit Eric T; Reich Hans J^*

来源：Organic Letters, 2015, 17(10): 2310-2313.

DOI：10.1021/acs.orglett.5b00650

Unexpectedly high rates of reaction between alkyllithium reagents and amides, compared to esters and ketones, were observed by Rapid Inject NMR and competition experiments. Spectroscopic investigations with 4-fluorophenyllithium (ArLi, mixture of monomer and dimer in THF) and a benzoate ester identified two reactive intermediates, a homodimer of the tetrahedral intermediate, stable below -100 degrees C, and a mixed dimer with ArLi. Direct formation of dimers suggested that the ArLi dimer may be the reactive aggregate rather than the usually more reactive monomer. In contrast, RINMR experiments with ketones demonstrated that the ArLi monomer was the reactive species.

• 出版日期2015-5-15