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Regio- and Diastereoselective Vicinal Aminobromination of Electron Deficient Olefins via Phosphorus-Based GAP Protocol.

ABSTRACT: Chemical synthesis based on Group-Assisted Purification chemistry (GAP) has been prolifically used as a powerful, greener and ecofriendly tool so far. Herein, we report hypervalent iodine (III) mediated regio- and diastereoselective aminobromination of electron-deficient olefins using group-assisted purification (GAP) method. By simply mixing the GAP auxiliary-anchored substrates with TsNH₂-NBS as nitrogen/bromine sources and PhI(OAc)₂ as a catalyst, a series of vicinal bromoamines with multifunctionalities were obtained in moderate to excellent yields (53-94%). The vicinal bromoamines were obtained without column chromatography and/or recrystallization simply by washing the crude mixtures with cosolvents and thus avoiding wastage of silica, solvents, time, and labor. The GAP auxiliary is recyclable and reusable.

SUBMITTER: Rahman AU

PROVIDER: S-EPMC8456122 | biostudies-literature | 2021

REPOSITORIES: biostudies-literature

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Regio- and Diastereoselective Vicinal Aminobromination of Electron Deficient Olefins via Phosphorus-Based GAP Protocol.

Rahman Anis Ur AU Zarshad Nighat N Khan Iltaf I Faiz Faisal F Li Guigen G Ali Asad A

Frontiers in chemistry 20210908

Chemical synthesis based on Group-Assisted Purification chemistry (GAP) has been prolifically used as a powerful, greener and ecofriendly tool so far. Herein, we report hypervalent iodine (III) mediated regio- and diastereoselective aminobromination of electron-deficient olefins using group-assisted purification (GAP) method. By simply mixing the GAP auxiliary-anchored substrates with TsNH<sub>2</sub>-NBS as nitrogen/bromine sources and PhI(OAc)<sub>2</sub> as a catalyst, a series of vicinal bro ...[more]

PMID: 34568286

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