Reacting an aldehyde with a Grignard reagent or organolithium and treating the resulting secondary alkoxide with N-tert-butylbenzenesulfinimidoyl chloride is a convenient one-pot reaction for converting aldehydes to ketones. While Grignards can be used for this reaction, organolithium compounds give higher yields, due to the higher reactivity of a lithium alkoxide compared to the corresponding magnesium salt. In some cases, an equivalent of DMPU, a Lewis base, will increase yields. For example, treating benzaldehyde with n-butyllithium and N-tert-butylbenzenesulfinimidoyl chloride in THF gives 1-phenyl-1-pentanone in good yield.
N-tert-Butylbenzenesulfinimidoyl chloride can also be used to synthesize imines from amines. Imines synthesized in this fashion have been shown to undergo a one-pot Mannich reaction with 1,3-dicarbonyl compounds, such as malonate esters and 1,3-diketones. In this example, Cbz-protected benzylamine is deprotonated using n-butyllithium, then treated with N-tert-butylbenzenesulfinimidoyl chloride to form the protected imine. Dimethyl malonate acts as the nucleophile and reacts with the imine to give the final product, a Mannich base.