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Protecting-Group-Free Amidation of Amino Acids using Lewis Acid Catalysts.

ABSTRACT: Amidation of unprotected amino acids has been investigated using a variety of 'classical" coupling reagents, stoichiometric or catalytic group(IV) metal salts, and boron Lewis acids. The scope of the reaction was explored through the attempted synthesis of amides derived from twenty natural, and several unnatural, amino acids, as well as a wide selection of primary and secondary amines. The study also examines the synthesis of medicinally relevant compounds, and the scalability of this direct amidation approach. Finally, we provide insight into the chemoselectivity observed in these reactions.

SUBMITTER: Sabatini MT

PROVIDER: S-EPMC5969221 | biostudies-other | 2018 May

REPOSITORIES: biostudies-other

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Protecting-Group-Free Amidation of Amino Acids using Lewis Acid Catalysts.

Sabatini Marco T MT Karaluka Valerija V Lanigan Rachel M RM Boulton Lee T LT Badland Matthew M Sheppard Tom D TD

Chemistry (Weinheim an der Bergstrasse, Germany) 20180430 27

Amidation of unprotected amino acids has been investigated using a variety of 'classical" coupling reagents, stoichiometric or catalytic group(IV) metal salts, and boron Lewis acids. The scope of the reaction was explored through the attempted synthesis of amides derived from twenty natural, and several unnatural, amino acids, as well as a wide selection of primary and secondary amines. The study also examines the synthesis of medicinally relevant compounds, and the scalability of this direct am ...[more]

PMID: 29505683

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