Copper pins on the boron: The enantioselective 1,4‐addition of diboron to α,β‐unsaturatedcompounds proceeds smoothly in the presence of catalytic amounts of Cu(OH)2 and chiral 2,2′‐bipyridine ligand in water. A wide substrate scope of α,β‐unsaturatedcarbonylcompounds, including acyclic, cyclic, and β,β‐disubstituted enones, α,β‐unsaturated esters, amides, and a nitrile, has been shown.
Heterogeneous versus Homogeneous Copper(II) Catalysis in Enantioselective Conjugate-Addition Reactions of Boron in Water
作者:Taku Kitanosono、Pengyu Xu、Shū Kobayashi
DOI:10.1002/asia.201300997
日期:2014.1
reported for the conjugateaddition of boron. Heterogeneous cat. 1 also gave high yields and enantioselectivities with some substrates and also gave the highest TOF (43 200 h−1) for an asymmetric conjugate‐additionreaction of boron. In addition, the catalyst systems were also applicable to the conjugateaddition of boron to α,β,γ,δ‐unsaturated carbonyl compounds, although such reactions have previously
Hantzsch Ester-Mediated Photochemical Transformations in the Ketone Series: Remote C(sp<sup>3</sup>)–H Arylation and Cyclopentene Synthesis through Strain Release
作者:Jan Paternoga、Jonas Kühlborn、Nils Ole Rossdam、Till Opatz
DOI:10.1021/acs.joc.0c02591
日期:2021.2.19
A metal-free Hantzsch ester-mediated synthesis of cyclopentenylketones as well as γ-hetarylketones starting from ketocyclopropanes under eco-friendly conditions was developed. The versatility of the developed conditions is shown by reacting ketocyclopropanes in both a formal [3 + 2] cycloaddition with terminal alkynes (further investigated using theoretical calculations) and a radical C–C-coupling
Strontium-Catalyzed Highly Enantioselective Michael Additions of Malonates to Enones
作者:Magno Agostinho、Shū Kobayashi
DOI:10.1021/ja710332h
日期:2008.2.1
A novel catalyst system based on a chiral strontium complex which promotes the catalytic asymmetric Michael addition reactions of malonates to enones has been developed. The conjugate addition reactions proceeded smoothly in the presence of 5 mol % of the chiral strontium catalyst, at room temperature, to afford the desired adducts in high yields and excellent enantioselectivities. This method provides