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One-pot synthesis of novel chiral ?-amino acid derivatives by enantioselective Mannich reactions catalyzed by squaramide cinchona alkaloids.

ABSTRACT: An ef?cient one-pot synthesis of novel ?-amino acid derivatives containing a thiadiazole moiety was developed using a chiral squaramide cinchona alkaloid as organocatalyst. The reactions afforded chiral ?-amino acid derivatives in moderate yields and with moderate to excellent enantioselectivities. The present study demonstrated for the first time the use of a Mannich reaction catalyzed by a chiral bifunctional organocatalyst for the one-pot synthesis of novel ?-amino acid derivatives bearing a 1,3,4-thiadiazole moiety on nitrogen.

SUBMITTER: Zhang K

PROVIDER: S-EPMC6270396 | biostudies-literature | 2013 May

REPOSITORIES: biostudies-literature

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One-pot synthesis of novel chiral β-amino acid derivatives by enantioselective Mannich reactions catalyzed by squaramide cinchona alkaloids.

Zhang Kankan K Liang Xueping X He Ming M Wu Jian J Zhang Yuping Y Xue Wei W Jin Linhong L Yang Song S Hu Deyu D

Molecules (Basel, Switzerland) 20130523 6

An efﬁcient one-pot synthesis of novel β-amino acid derivatives containing a thiadiazole moiety was developed using a chiral squaramide cinchona alkaloid as organocatalyst. The reactions afforded chiral β-amino acid derivatives in moderate yields and with moderate to excellent enantioselectivities. The present study demonstrated for the first time the use of a Mannich reaction catalyzed by a chiral bifunctional organocatalyst for the one-pot synthesis of novel β-amino acid derivatives bearing a ...[more]

PMID: 23702920

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