Stereocontrolled Ring-Opening of a Hindered Sulfamidate with Nitrogen-Containing Aromatic Heterocycles: Synthesis of Chiral Quaternary Imidazole Derivates
- Mata, L. 1
- Jiménez-Osés, G. 2
- Avenoza, A. 1
- Busto, J.H. 1
- Peregrina, J.M. 1
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1
Universidad de La Rioja
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2
University of California Los Angeles
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ISSN: 0022-3263
Ano de publicación: 2011
Volume: 76
Número: 10
Páxinas: 4034-4042
Tipo: Artigo
Outras publicacións en: Journal of Organic Chemistry
Resumo
This paper explores the role of a hindered cyclic sulfamidate derived from α-methylisoserine as an electrophile in a nucleophilic displacement reaction with nitrogen-containing aromatic heterocycles. Several imidazoles and pyrazole were tested as nucleophiles in the absence of an additional base to give the corresponding ring-opening compounds. We show that the process takes place by inversion of the configuration of the quaternary electrophilic center, retaining the enantiomeric excess of the starting sulfamidate. This reaction opens the way to obtain important quaternary imidazole derivatives such as an innovative type of bis-amino acid related to histidinoalanine and a novel α,α-disubstituted β-amino acid (β2,2-amino acid). © 2011 American Chemical Society.