Synthesis of N-Vinyloxazolidinones and Morpholines from Amino Alcohols and Vinylsulfonium Salts: Analysis of the Outcome's Dependence on the N-Protecting Group by Nanospray Mass Spectrometry



The effect of the nature of the N-protecting group on 1,2-amino alcohols in annulation reactions with diphenylvinylsulfonium triflate has been investigated. Although tosyl and sulfinamide groups give morpholines in high yields, the use of N-Cbz leads to a high-yielding synthesis of N-vinyloxazolidinones. The reactions were monitored by nanospray MS/MS, which revealed why reactions are successful and the fate of reactive intermediates in the unsuccessful reactions.