Catalytic enantioselective C-H functionalization of indoles with α-diazopropionates using chiral dirhodium(II) carboxylates : asymmetric synthesis of the (+)-α-methyl-3-indolylacetic acid fragment of acremoauxin A
Abstract
An enantioselective C-H functionalization of N-methoxymethyl (MOM)-protected 2,3-unsubstituted indoles with α-diazopropionates has been effected under catalysis by dirhodium(II) tetrakis[N-phthaloyl-(S)-triethylalaninate], Rh2(S-PTTEA)4, providing α-methyl-3-indolylacetates in high yields and with enantioselectivities of up to 86% ee. The effectiveness of this protocol was demonstrated by the first catalytic asymmetric synthesis of the (+)-α-methyl-3-indolylacetic acid fragment of acremoauxin A, a potent plant-growth inhibitor. Furthermore, the Fujioka protocol using a combination of TMSOTf and 2,2'-bipyridyl was shown to be superior for the removal of the N-MOM group.
Journal
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- Tetrahedron : Asymmetry
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Tetrahedron : Asymmetry 22 (8), 907-915, 2011-04-30
Elsevier
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Details
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- CRID
- 1050001339008450560
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- NII Article ID
- 120003260036
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- HANDLE
- 2115/46945
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- ISSN
- 09574166
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- Text Lang
- en
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- Article Type
- journal article
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- Data Source
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- IRDB
- CiNii Articles