Saturated oxygen and nitrogen heterocycles via oxidative coupling of alkyltrifluoroborates with alkenols, alkenoic acids and protected alkenylamines

Abstract

The oxidative coupling of alkyltrifluoroborates with heteroatom-tethered vinylarenes leads to a broad range of saturated oxygen and nitrogen heterocycles.

Synthesis of Benzylureas and Related Amine Derivatives via Copper-Catalyzed Three-Component Carboamination of Styrenes

“…Support for this mechanism includes the sensitivity to steric hindrance at the benzylic carbon as tertiary benzylureas are not formed (a 1,1-disubstituted alkene did not produce 3 ). Both the carbocation mechanisms ,, and carbon radical mechanisms have previously been proposed for related metal-catalyzed three-component alkene carboaminations involving radical intermediates, and it is probable that both pathways are viable. , …”

“…21,25,26 An alternative threecomponent alkene carboamination has also been accomplished using a directing group strategy involving polar addition to nonconjugated carbonyl-functionalized alkenes. 27,28 We [29][30][31] and others [32][33][34][35] have disclosed that potassium alkyltrifluoroborates are an excellent source of alkyl radicals. 36 Alkyl radicals generated from alkyltrifluoroborates can be primary, secondary, or tertiary and do not need to contain specific functionality such as carbonyls, nitriles, or multiple halides.…”

“…We − and others − have disclosed that potassium alkyltrifluoroborates are an excellent source of alkyl radicals . Alkyl radicals generated from alkyltrifluoroborates can be primary, secondary, or tertiary and do not need to contain specific functionality such as carbonyls, nitriles, or multiple halides.…”

“…36 Alkyl radicals generated from alkyltrifluoroborates can be primary, secondary, or tertiary and do not need to contain specific functionality such as carbonyls, nitriles, or multiple halides. In particular, the formation of benzylic radicals from potassium benzyltrifluoroborates occurs readily 29,31 and may offer advantages over other radical generating approaches where examples involving benzylic radical intermediates in such couplings are lacking. In addition, alkyltrifluoroborates offer a higher degree of stability, compared to alternative general alkyl radical precursors (for example, peroxides).…”

Critical Ligand and Salt Effects in Organomagnesiate‐Promoted 3,3‐Disubstituted Phthalides Synthesis from 2‐Iodobenzoate Derivatives

“…However, R 1 of the product come from the starting material. This route used ortho ‐carboxy styrene as starting material via a copper‐catalyzed reaction involving bromo‐derivatives [19] or organotrifluoroborates [20] as coupling partner or via an arylation‐lactonization sequence involving primary amines [21] …”