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Approach to vicinal t-Boc-amino dibromides via catalytic aminobromination of nitrostyrenes without using chromatography and recrystallization.

ABSTRACT: A 1.0 mol % amount of K(3)PO(4)·3H(2)O was found to catalyze aminohalogenation reaction of nitrostyrenes with N,N-dibromo-tert-butylcarbamate (t-Boc-NBr(2)) in a dichloroethane system. Good to excellent yields and complete regioselectivity have been achieved by taking advantage of the GAP workup without using traditional purification techniques such as column chromatography and recrystallization. Anew mechanism is proposed involving radical and ionic catalytic cycles and an intramolecular migration.

SUBMITTER: Sun H

PROVIDER: S-EPMC3568972 | biostudies-literature | 2013 Feb

REPOSITORIES: biostudies-literature

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Approach to vicinal t-Boc-amino dibromides via catalytic aminobromination of nitrostyrenes without using chromatography and recrystallization.

Sun Hao H Han Jianlin J Kattamuri Padmanabha V PV Pan Yi Y Li Guigen G

The Journal of organic chemistry 20130123 3

A 1.0 mol % amount of K(3)PO(4)·3H(2)O was found to catalyze aminohalogenation reaction of nitrostyrenes with N,N-dibromo-tert-butylcarbamate (t-Boc-NBr(2)) in a dichloroethane system. Good to excellent yields and complete regioselectivity have been achieved by taking advantage of the GAP workup without using traditional purification techniques such as column chromatography and recrystallization. Anew mechanism is proposed involving radical and ionic catalytic cycles and an intramolecular migrat ...[more]

PMID: 23311641

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