Chiral Auxiliary Approach for Gold(I)-Catalyzed Cyclizations.

Autor: Cataffo A; Institute of Chemical Research of Catalonia (ICIQ), CERCA, Barcelona Institute of Science and Technology, Av. Països Catalans 16, 43007, Tarragona, Spain.; Departament de Química Analítica i Química Orgànica, Universitat Rovira i Virgili, C/Marcel⋅lí Domingo s/n, 43007, Tarragona, Spain., Peña-López M; Institute of Chemical Research of Catalonia (ICIQ), CERCA, Barcelona Institute of Science and Technology, Av. Països Catalans 16, 43007, Tarragona, Spain.; Departament de Química Analítica i Química Orgànica, Universitat Rovira i Virgili, C/Marcel⋅lí Domingo s/n, 43007, Tarragona, Spain., Pedrazzani R; Institute of Chemical Research of Catalonia (ICIQ), CERCA, Barcelona Institute of Science and Technology, Av. Països Catalans 16, 43007, Tarragona, Spain.; Departament de Química Analítica i Química Orgànica, Universitat Rovira i Virgili, C/Marcel⋅lí Domingo s/n, 43007, Tarragona, Spain., Echavarren AM; Institute of Chemical Research of Catalonia (ICIQ), CERCA, Barcelona Institute of Science and Technology, Av. Països Catalans 16, 43007, Tarragona, Spain.; Departament de Química Analítica i Química Orgànica, Universitat Rovira i Virgili, C/Marcel⋅lí Domingo s/n, 43007, Tarragona, Spain.
Jazyk: angličtina
Zdroj: Angewandte Chemie (International ed. in English) [Angew Chem Int Ed Engl] 2023 Dec 04; Vol. 62 (49), pp. e202312874. Date of Electronic Publication: 2023 Nov 06.
DOI: 10.1002/anie.202312874
Abstrakt: Two different classes of stereoselective cyclizations have been developed using a chiral auxiliary approach with commercially available [JohnPhosAu(MeCN)SbF 6 ] as catalyst. First, a stereoselective cascade cyclization of 1,5-enynes was achieved using the Oppolzer camphorsultam as chiral auxiliary. In this case, a one-pot cyclization-hydrolysis sequence was developed to directly afford enantioenriched spirocyclic ketones. Then, the stereoselective alkoxycyclization of 1,6-enynes was mediated by an Evans-type oxazolidinone. A reduction-hydrolysis sequence was selected to remove the auxiliary to give enantioenriched β-tetralones. DFT studies confirmed that the steric clash between the chiral auxiliary and alkene accounts for the experimentally observed diastereoselective cyclization through the Si face.
(© 2023 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)
Databáze: MEDLINE
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