Restoration of catalytic activity by the preservation of ligand structure: Cu-catalysed asymmetric conjugate addition with 1,1-diborylmethane

Abstract

A novel Cu-catalysed asymmetric conjugate addition reaction with bis[(pinacolato)boryl]methane using α,β-unsaturated enones as substrates has been developed on the basis of strategic preservation of the supporting ligand.

Robust dicopper(i) μ-boryl complexes supported by a dinucleating naphthyridine-based ligand

“…S13 † ). 16 Altogether, these data suggest the formation of boryl complex [(DPFN)Cu 2 (μ-Bpin)][NTf 2 ] (2, Scheme 3 ).…”

Alkenylboronic Ester Activation to Nucleophilic Addition and Electrophilic Trapping with Carbonyl Groups

“…In all the examples described, a new tetrasubstituted carbon center has been formed from 1-phenylvinylboronic acid pinacol ester substrate. It is noteworthy to mention that α-boryl carbanion-based conjugate additions remains scarcely explored, and the unique methods reported so far involve deborylation of geminal triboryl 25 and diborylalkanes 26,27 or alternative Template for SYNLETT Thieme activation of diboryl allylic systems. 28 α-Boryl C(sp 2 ) nucleophiles can also be added to enones through 1,4-addition in the presence of Rh catalysts.…”

Recent Advances in Nonprecious Metal Catalysis

“…Lee and co-workers reported the Cu-catalyzed asymmetric conjugate addition of 1,1-diborylmethane (BPin-CH 2 -BPin) to α,β-unsaturated enones (Scheme 42). 105 A phosphor-amidite ligand, (S)-MonoPhos, was found to be the optimal ligand. The addition of Li(acac) was crucial to the success of the reaction.…”