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N-Heterocyclic Carbene Catalyzed Enantioselective Annulation of Benzothiazolyl Ethyl Acetates with 2-Bromoenals.

ABSTRACT: An N-heterocyclic carbene catalyzed enantioselective [3+3] annulation of benzothiazolyl acetates with 2-bromoenals has been developed. The protocol provides a direct asymmetric synthesis of dihydro-1H-benzothiazolopyridinones in good to very good yields and medium ee values. In many cases, the virtually enantiopure heterocycles are available through a single recrystallization (99% ee).

SUBMITTER: Ni Q

PROVIDER: S-EPMC4702349 | biostudies-literature | 2015 Jun

REPOSITORIES: biostudies-literature

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N-Heterocyclic Carbene Catalyzed Enantioselective Annulation of Benzothiazolyl Ethyl Acetates with 2-Bromoenals.

Ni Qijian Q Xiong Jiawen J Song Xiaoxiao X Raabe Gerhard G Enders Dieter D

Synlett : accounts and rapid communications in synthetic organic chemistry 20150601 11

An N-heterocyclic carbene catalyzed enantioselective [3+3] annulation of benzothiazolyl acetates with 2-bromoenals has been developed. The protocol provides a direct asymmetric synthesis of dihydro-1<i>H</i>-benzothiazolopyridinones in good to very good yields and medium ee values. In many cases, the virtually enantiopure heterocycles are available through a single recrystallization (99% ee). ...[more]

PMID: 26752810

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