Visible Light-Induced Selective Generation of Radicals from Organoborates by Photoredox Catalysis
作者:Yusuke Yasu、Takashi Koike、Munetaka Akita
DOI:10.1002/adsc.201200588
日期:2012.12.14
A new strategy for the generation of carbon-centered radicals via oxidation of alkyl-, allyl-, benzyl- and arylborates by visible-light-driven single electron transfer (SET) photoredoxcatalysis has been established. The generated radicals smoothly react with TEMPO and electron-deficient alkenes to afford CO and CC coupling products, respectively. In this radical initiating system, cyclic organo(triol)borates
Direct Boronation of Allyl Alcohols with Diboronic Acid Using Palladium Pincer-Complex Catalysis. A Remarkably Facile Allylic Displacement of the Hydroxy Group under Mild Reaction Conditions
作者:Vilhelm J. Olsson、Sara Sebelius、Nicklas Selander、Kálmán J. Szabó
DOI:10.1021/ja060468n
日期:2006.4.1
to allyl boronic acids and subsequently to trifluoro(allyl)borates with tetrahydroxy diboron using palladium pincer-complex catalysis. These reactions are regio- and stereoselective proceeding with high isolated yields. Competitive boronation experiments indicate that under the applied reaction conditions the allylic displacement of a hydroxy group is faster than the displacement of an acetate leaving
Enantioselective Rhodium-Catalyzed Allylation of Cyclic Imines with Potassium Allyltrifluoroborates
作者:Hon Lam、Hamish Hepburn、Nawasit Chotsaeng、Yunfei Luo
DOI:10.1055/s-0033-1339499
日期:——
position of the boron atom. Representative examples of manipulation of the products are also described. This article presents further examples of the enantioselective rhodium-catalyzed addition of potassium allyltrifluoroborates to cyclicimines. A wide range of substituted allyl-trifluoroborates are compatible with this process, and provide protected homoallylic amines with high levels of diastereo- and
The unprecedented development of asymmetric Rh-catalyzed 1,2-allylation of N-Ts- and N-Ns-aldimines is achieved. This protocol utilizes potassium allyltrifluoroborates and various aldimines to generate enantioenriched homoallylic amines in the presence of 3.0 mol % of Rh(I)/L1b catalyst with up to 90% yield, 98% ee (R = H), and 10:1 diastereoselectivity (R = Me or Ph), yielding the same major diastereomer
Performance of SCS Palladium Pincer Complexes in Borylation of Allylic Alcohols. Control of the Regioselectivity in the One-Pot Borylation−Allylation Process
作者:Nicklas Selander、Kálmán J. Szabó
DOI:10.1021/jo9008673
日期:2009.8.7
One-pot borylation-allylation reactions of aldehydes and allylic alcohols were performed under various reaction conditions. The borylation of allylic alcohols was performed using a very efficient SCS palladium pincer-complex catalyst. The regioselectivity of the allylation depends on the applied solvent. The reaction in CHCl3 gave the linear allylic product; however, when MeOH was added to the reaction mixture, the branched allylic product was formed.