Chemistry of Amino Acids. II. Studies on α-Alkyl-α-Amino Acids. I. Abnormal Decarbonylation of α-Methyl-α-phenylglycine
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چکیده
منابع مشابه
Synthesis of quaternary α-methyl α-amino acids by asymmetric alkylation of pseudoephenamine alaninamide pivaldimine.
The utility of pseudoephenamine as a chiral auxiliary for the alkylative construction of quaternary α-methyl α-amino acids is demonstrated. The method is notable for the high diastereoselectivities of the alkylation reactions, for its versatility with respect to electrophilic substrate partners, and for its mild hydrolysis conditions, which provide α-amino acids without salt contaminants. Alter...
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Complex amino acids with an α-acyloxycarbonyl functionality in the side chain are easily available through epoxide opening by chelated enolates and subsequent oxidation/Passerini reaction. This protocol works with both, aldehyde and ketone intermediates, as long as the ketones are activated by electron-withdrawing groups. In principle Ugi reactions are also possible, allowing the generation of ...
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ژورنال
عنوان ژورنال: Chemical and Pharmaceutical Bulletin
سال: 1965
ISSN: 0009-2363,1347-5223
DOI: 10.1248/cpb.13.1001