Cu(i)-catalyzed enantioselective and stereospecific borylative annulation of cyclic 1,3-dione-tethered 1,3-enynes
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Updated: Sep 14, 2025

A Two-Step Protocol for Umpolung Functionalization of Ketones Via Enolonium Species
Published on: August 16, 2018
G Raghu Ramudu1,2, Vaibhav B Patil1, Jagadeesh Babu Nanubolu3,2
1Department of Organic Synthesis and Process Chemistry, CSIR-Indian Institute of Chemical Technology (CSIR-IICT) Hyderabad 500007 India rchegondi@iict.res.in cramhcu@gmail.com https://www.cramhcu.wixsite.com/rambabu-chegondi.
Abstract:
A copper(i)-catalyzed, highly enantioselective, and diastereoselective borylative cyclization of prochiral cyclic 1,3-dione-tethered 1,3-enynes is reported. This stereospecific transformation exhibits a broad substrate scope, enabling access to bicyclic organoboron products containing four contiguous stereocenters with excellent enantioselectivity. Notably, the reaction rate is significantly influenced by the substrate's stereochemistry, with the (Z)-isomer undergoing borylative cyclization much faster than the (E)-isomer due to reduced steric interactions during C-C bond formation. Furthermore, treatment of the resulting products with sodium perborate yields the corresponding alcohols without compromising enantiomeric excess.
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