Catalytic enantioselective synthesis of perfluoroalkyl-substituted β-lactones via a concerted asynchronous [2 + 2] cycloaddition: a synthetic and computational study.

ABSTRACT: The enantioselective preparation of a range of perfluoroalkyl-substituted β-lactones through an isothiourea (HyperBTM) catalysed reaction using symmetric anhydrides as ammonium enolate precursors and perfluoroalkylketones (R_F = CF₃, C₂F₅, C₄F₉) is reported. Following optimisation, high diastereo- and enantioselectivity was observed for β-lactone formation using C₂F₅- and C₄F₉-substituted ketones at room temperature (26 examples, up to >95 : 5 dr and >99 : 1 er), whilst -78 °C was necessary for optimal dr and er with CF₃-substituted ketones (11 examples, up to >95 : 5 dr and >99 : 1 er). Derivatisation of the β-lactones through ring-opening, as well as a two-step conversi

SUBMITTER: Barrios Antunez DJ 

PROVIDER: S-EPMC6585878 | biostudies-literature | 2019 Jun

REPOSITORIES: biostudies-literature