an aromaticaldehyde for use in asymmetric synthesis. The reaction between aromaticaldehydes and aryl or allyl electrophiles with a silylboronate utilizing a chiral copper-N-heterocyclic carbene catalyst and a palladium-bisphosphine catalyst in a synergistic manner occurred with high enantioselectivities to deliver the three-component coupling products, chiral silyl-protected secondary alcohol derivatives
reaction of aromaticaldehydes and arylketones with a silylboronate in the presence of a catalytic amount of a CuCl-N-heterocyclic carbene (NHC) complex and a stoichiometric amount of alkoxide base yielded cross-coupled 1,2-diol derivatives. A reaction pathway is proposed that involves the catalytic formation of a nucleophilic α-silyloxybenzylcopper(I) species from the aromaticaldehyde and its subsequent
Access to Enantioenriched Benzylic 1,1-Silylboronate Esters by Palladium-Catalyzed Enantiotopic-Group Selective Suzuki–Miyaura Coupling of (Diborylmethyl)silanes with Aryl Iodides
作者:Junghoon Kim、Seung Hwan Cho
DOI:10.1021/acscatal.8b03979
日期:2019.1.4
This work describes the palladium-catalyzed enantiotopic-group selective Suzuki–Miyaura cross-coupling of (diborylmethyl)silanes with aryl iodides. The combination of a Pd(TFA)2 and rev-Josiphos-type ligand bearing a 3,5-bis(trifluoromethyl)phenyl as benzylic phosphine substituent in the presence of NaI as an additive and NaOMe as a base promotes the reaction to high efficiency and enantioselectivity
How to train your silane: A new family of chiral copper(I) complexes that bear a bifluoride counteranion were prepared and used in the first example of the enantioselective transfer of a silylgroup to an aldehyde. This procedure provides fast access to non‐racemic α‐hydroxysilanes in high enantioselectivities.
Metal-free catalytic enantioselective silylation of aromatic aldehydes in water
作者:Yuwen Huo、Panpan Shen、Wenzeng Duan、Zhen Chen、Chun Song、Yudao Ma
DOI:10.1016/j.cclet.2017.12.005
日期:2018.9
metal-free method for the preparation of chiral α-hydroxysilanes was developed. Enantioselective addition of a silicon nucleophile to aromatic aldehydes in water was achieved by using a new hydroxyl-functionalized chiral carbene as catalyst, affording the corresponding products in good yields and moderate enantioselectivities.