2024-03-28T10:27:12Zhttps://eprints.lib.hokudai.ac.jp/dspace-oai/requestoai:eprints.lib.hokudai.ac.jp:2115/469452022-11-17T02:08:08Zhdl_2115_20044hdl_2115_124Catalytic 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 AGoto, TakayukiNatori, YoshihiroTakeda, KojiNambu, HisanoriHashimoto, Shunichi499An 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.ElsevierJournal Articleapplication/pdfhttp://hdl.handle.net/2115/46945https://eprints.lib.hokudai.ac.jp/dspace/bitstream/2115/46945/1/TetA22-8_907-915.pdf0957-4166Tetrahedron : Asymmetry2289079152011-04-30enginfo:doi/10.1016/j.tetasy.2011.05.011author