Journal of the American Chemical Society 2005-12-28

Expedient synthesis of cyclopropane alpha-amino acids by the catalytic asymmetric cyclopropanation of alkenes using iodonium ylides derived from methyl nitroacetate.

Benoît Moreau, André B Charette

Index: J. Am. Chem. Soc. 127(51) , 18014-5, (2005)

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Abstract

A highly enantioselective (up to 97.5% ee) and diastereoselective (95:5 dr trans/cis) Cu(I)-catalyzed cyclopropanation of alkenes using phenyliodonium ylide generated in situ from iodosobenzene and methyl nitroacetate is reported. The cyclopropanation took place with high enantioselectivity for a wide range of alkenes, and the reaction was performed at room temperature. 1-Nitrocyclopropyl esters are versatile building blocks to access the corresponding cyclopropane amino esters and aminocyclopropanes in two and three steps, respectively, from commercially available products.