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Electrochemical Dehydrogenative C(sp² )-H Amination.

ABSTRACT: A transition-metal-free direct electrolytic C-H amination involving an electrochemically generated nitrenium ion intermediate has been developed. The electrosynthesis takes place in the absence of any organoiodine catalysts and is enabled by an in situ generated electrolyte. A novel, efficient intramolecular and intermolecular C-H amination has been demonstrated using a simple reaction setup.

SUBMITTER: Puthanveedu M

PROVIDER: S-EPMC8251997 | biostudies-literature |

REPOSITORIES: biostudies-literature

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Copper-catalyzed dehydrogenative γ-C(sp3)-H amination of saturated ketones for synthesis of polysubstituted anilines.

Project description:Metal-catalyzed β-C-H functionalization of saturated carbonyls via dehydrogenative desaturation proved to be a powerful tool for simplifying synthesis of valuable β-substituted carbonyls. Here, we report a copper-catalyzed dehydrogenative γ-C(sp3)-H amination of saturated ketones that initiates the three-component coupling of saturated ketones, amines and N-substituted maleimides to construct polysubstituted anilines. The protocol presented herein enables both linear and α-branched butanones to couple a wide spectrum of amines and various N-substituted maleimides to produce diverse tetra- or penta-substituted anilines in fair-to-excellent yields with good functional group tolerance. The mechanism studies support that this ketone dehydrogenative γ-C(sp3)-H amination was triggered by the ketone α,β-dehydrogenation desaturation that activates the adjacent γ-C(sp3)-H bond towards functionalization. This α,β-dehydrogenation desaturation-triggered cascade sequence opens up a new avenue to the remote C(sp3)-H functionalization of saturated ketones and has the potential to enable the rapid syntheses of complex compounds from simple starting materials.

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Merging Photochemistry with Electrochemistry: Functional-Group Tolerant Electrochemical Amination of C(sp3 )-H Bonds.

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Cobalt-catalysed site-selective intra- and intermolecular dehydrogenative amination of unactivated sp(3) carbons.

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