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Please login to access the full content or check if you have access via Copper-Catalyzed Borylative Ring Closing of Aryl- and Hetaryl-Substituted Allylic Phosphates

DOI: 10.1055/sos-SD-230-00106

Kubota, K.; Ito, H.Science of Synthesis: Advances in Organoboron Chemistry towards Organic Synthesis, (20191228.

A similar procedure is effective for the enantioselective synthesis of aryl- and hetaryl-substituted cyclopropylboronates 5 from Z-allylic phosphates 4 and bis(pinacolato)diboron (2) in good to high yields with excellent enantioselectivities using copper(I) chloride as copper catalyst and a chiral ligand (Scheme 2).[‌2‌] The reaction shows excellent diastereoselectivity and good functional-group compatibility. Optimized enantioselectivity is achieved when (R,R)-iPr-DuPhos is used as chiral ligand. When E-allylic phosphates are used as substrates, the products switch from the trans to the cis configuration in the presence of (R,R)-iPr-DuPhos.

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