Javier Carreras, Ana Caballero and Pedro J. Pérez
Useful handles: 1-Boryl-2,3-disubstituted cyclopropanes can be prepared in high yield and high diastereo- and enantioselectivity from alkenylboronates and ethyl diazoacetate in the presence of catalytic amounts of a copper(I) bisoxazoline species. The resulting cyclopropanes are versatile synthetic intermediates that can undergo further transformations at the carbon–boron bond.
Angew. Chem. Int. Ed. 2018, 57, 2334; doi: 10.1002/anie.201710415