Aldehydes as alkyl carbanion equivalents for additions to carbonyl compounds
作者:Haining Wang、Xi-Jie Dai、Chao-Jun Li
DOI:10.1038/nchem.2677
日期:2017.4
ruthenium catalyst and diphosphine ligand under mild conditions, delivering synthetically valuable secondary and tertiary alcohols in up to 98% yield. The unique chemoselectivity exhibited by carbonyl-derived carbanion equivalents is demonstrated by their tolerance to protic reaction media and good functional group compatibility. Enantioenriched tertiary alcohols can also be accessed with the aid of chiral
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
Enantioselective Construction of Tertiary Boronic Esters by Conjunctive Cross-Coupling
作者:Jesse A. Myhill、Liang Zhang、Gabriel J. Lovinger、James P. Morken
DOI:10.1002/anie.201807775
日期:2018.9.24
Catalytic enantioselectiveconjunctive cross‐coupling has been developed to construct tertiary alkylboronic esters. These reactions occur with good yield and enantioselectivity for a range of substrates. Mechanistic experiments reveal aspects of the catalytic cycle that allow hindered substrates to react without significant complicating side reactions.
Improved method for the conversion of pinacolboronic esters into trifluoroborate salts: facile synthesis of chiral secondary and tertiary trifluoroborates
作者:Viktor Bagutski、Abel Ros、Varinder K. Aggarwal
DOI:10.1016/j.tet.2009.10.002
日期:2009.11
A general method for the preparation of virtually any potassium trifluoroborate salt from the corresponding pinacolboronic ester is reported. Thus, conditions for an azeotropic removal of pinacol from the reaction mixture were found to afford the desired potassium trifluoroborates of sufficient purity (>95%) in nearly quantitative yields irrespective of the nature of the product. The utility of this