Enantioselective Synthesis of 1- and 4-Hydroxytetrahydrocarbazoles through Asymmetric Transfer Hydrogenation
Keyword(s):
Several 1- and 4-hydroxytetrahydrocarbazoles were prepared in high yields (up to 99%) and excellent enantiomeric excesses (up to >99% ee) from the corresponding 1- and 4-oxotetrahydrocarbazoles through asymmetric transfer hydrogenation by using the commercially available Noyori–Ikariya ruthenium catalyst. The immediate use of the freshly prepared catalyst and the use of a HCO2H–DABCO (11:6) mixture as the hydrogen source are crucial for achieving high activity and enantioselectivity. In this way, a tetrahydrocarbazole heterocycle fused to a lactone moiety was synthesized in 45% yield and 97% ee.
2015 ◽
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pp. 6503-6514
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2019 ◽
Vol 361
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pp. 4106-4110
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2013 ◽
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pp. 196-201
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2009 ◽
Vol 298
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pp. 31-35
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2014 ◽
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pp. 2666-2681
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2005 ◽
Vol 136
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pp. 1619-1627
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