α‐Thianthrenium Carbonyl Species: The Equivalent of an α‐Carbonyl Carbocation

Angewandte Chemie, Год журнала: 2022, Номер 134(39)

Опубликована: Июль 27, 2022

Abstract Here we report an α‐thianthrenium carbonyl species, as the equivalent of α‐carbonyl carbocation, which is generated by radical conjugate addition a trifluoromethyl thianthrenium salt to Michael acceptors. The reactivity allows for synthesis C α ‐tetrasubstituted α‐ and β‐amino acid analogues via Ritter reaction acetonitrile. Addition hydroxide, methoxide, even fluoride can afford α‐heteroatom substituted α‐phenylpropanoates.

Язык: Английский

α‐Acylation of Alkenes by a Single Photocatalyst

Angewandte Chemie, Год журнала: 2022, Номер 134(52)

Опубликована: Окт. 7, 2022

Abstract A direct strategy for the difunctionalization of alkenes, with acylation occurring at more substituted alkene position, would be attractive complex ketone synthesis. We report herein a reaction driven by single photocatalyst that enables α‐acylation in this way introduction fluoromethyl, alkyl, sulfonyl or thioether group β‐position high chemo‐ and regioselectivity under extremely mild conditions. Crucial to success method are rate differences kinetics radical generation through single‐electron transfer (SET) between different precursors excited (PC*). Thus, is first occupied derived from precursor can generated most readily, α‐keto acids could used as an electrophilic reagent alkenes.

Язык: Английский