Asymmetric intramolecular Pauson-Khand reaction mediated by a remote sulfenyl or sulfinyl group.
In this work, we report the use of the asymmetric intramolecular Pauson-Khand reactions of 4-aryl-4-cyano-1,6-enynes for obtaining enantiomerically enriched bicyclo[3.3.0]octenones, and the influence of both the quaternary stereocenter and the sulfur functions located at ortho-position of the aryl group, on their stereoselectivity and reactivity. The sulfenyl derivatives bearing substituted or unsubstituted triple bonds and mono- and disubstituted alkene moieties afford bicyclo[3.3.0]octenones in high yields with complete diastereocontrol. These results are explained by assuming the association of the lone electron pair at sulfur to the Co-alkyne complexes.
Departamento de Química Orgánica (Módulo 01), Facultad de Ciencias, Universidad Autónoma de Madrid, Cantoblanco 28049 Madrid, Spain. joseluis.garcia.ruano@uam.es
José Luis
JL
García Ruano
Esther
E
Torrente
Alejandro
A
Parra
José
J
Alemán
Ana M
AM
Martín-Castro