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Highly Enantioselective Iridium-Catalyzed Hydrogenation of Cyclic Enamides.

ABSTRACT: The MaxPHOX-Ir catalyst system provided the highest selectivity ever reported for the reduction of cyclic enamides derived from ?- and ?-tetralones. This result indicates that iridium catalysts are also proficient in reducing alkenes bearing metal-coordinating groups. In the present system, selectivity was pressure-dependent: In most cases, a decrease in the H2 pressure to 3?bar resulted in an increase in enantioselectivity. Moreover, the process can be carried out in environmentally friendly solvents, such as methanol and ethyl acetate, with no loss of selectivity.

SUBMITTER: Salomo E

PROVIDER: S-EPMC5084810 | biostudies-other | 2016 Jul

REPOSITORIES: biostudies-other

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Highly Enantioselective Iridium-Catalyzed Hydrogenation of Cyclic Enamides.

Salomó Ernest E Orgué Sílvia S Riera Antoni A Verdaguer Xavier X

Angewandte Chemie (International ed. in English) 20160517 28

The MaxPHOX-Ir catalyst system provided the highest selectivity ever reported for the reduction of cyclic enamides derived from α- and β-tetralones. This result indicates that iridium catalysts are also proficient in reducing alkenes bearing metal-coordinating groups. In the present system, selectivity was pressure-dependent: In most cases, a decrease in the H2 pressure to 3 bar resulted in an increase in enantioselectivity. Moreover, the process can be carried out in environmentally friendly so ...[more]

PMID: 27186653

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