Enantioselective Intramolecular CH - Insertions upon Cu - Catalyzed Decomposition of Phenyliodonium Ylides . †
نویسندگان
چکیده
The Cu-catalyzed intramolecular CH insertion of phenyliodonium ylide 5b has been investigated at 0° C in the presence of several chiral ligands. Enantioselectivities vary in the range of 38–72 %, and are higher than those resulting from reaction of the diazo compound 5c at 65° C. The results are consistent with a carbenoid mechanism for Cu-catalyzed decomposition of phenyliodonium ylides.
منابع مشابه
Nickel(ii)-catalyzed enantioselective cyclopropanation of 3-alkenyl-oxindoles with phenyliodonium ylide via free carbene† †Electronic supplementary information (ESI) available. CCDC 1038443 and 1038445. For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c5sc03658e Click here for additional data file. Click here for additional data file.
The catalytic asymmetric cyclopropanation of a C]C double bond provides efficient access to optically active cyclopropane derivatives that are essential motifs in natural products and valuable building blocks for various transformations. Chiral transition-metal-catalyzed carbene transfer, such as that using Cu(I)-, Rh(II)-, Ru(II)-, and Co(II)-complexes with diazo compounds, permits such cylcop...
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