1142813-41-9Relevant academic research and scientific papers
Nickel-Catalyzed Asymmetric Hydroarylation of Vinylarenes: Direct Enantioselective Synthesis of Chiral 1,1-Diarylethanes
Tran, Hai N.,Burgett, Russell W.,Stanley, Levi M.
, p. 3836 - 3849 (2021/03/01)
The enantioselective hydroarylation of vinylarenes catalyzed by a chiral, non-racemic nickel catalyst is presented as a facile method to generate chiral 1,1-diarylethanes. These reactions proceed via formation of a chiral, non-racemic nickel benzyl intermediate. Transmetalation with arylboron nucleophiles and subsequent reductive elimination enable the formation of a variety of chiral 1,1-diarylethanes. The 1,1-diarylethane products from reactions of arylboronic acids containing electron-donating substituents are formed with typically greater than 90% ee, while the 1,1-diarylethanes generated from reactions of arylboronic acids containing electron-withdrawing groups are generated with typically less than 80% ee. These results are consistent with the rate of transmetalation with an arylboron nucleophile playing a key role in the enantioselectivity of these hydroarylation reactions. This mechanistic insight has led to the development of reactions of neo-pentylglycolate esters of arylboronic acids with vinylarenes that occur with higher enantioselectivities based on increased rates of transmetalation.
Highly chemoselective and enantiospecific Suzuki-Miyaura cross-couplings of benzylic organoboronic esters
Glasspoole, Ben W.,Oderinde, Martins S.,Moore, Brandon D.,Antoft-Finch, Aurora,Crudden, Cathleen M.
, p. 1759 - 1763 (2013/07/26)
The use of potassium carbonate in addition to silver oxide is shown to increase the enantiospecificity of the Suzuki-Miyaura cross-coupling reaction of chiral secondary benzylic boronic esters. From mechanistic studies, it is shown that the reaction is co
Protodeboronation of tertiary boronic esters: Asymmetric synthesis of tertiary alkyl stereogenic centers
Nave, Stefan,Sonawane, Ravindra P.,Elford, Tim G.,Aggarwal, Varinder K.
, p. 17096 - 17098 (2011/03/01)
While tertiary boranes undergo efficient protodeboronation with carboxylic acids, tertiary boronic esters do not. Instead, we have discovered that CsF with 1.1 equiv of H2O (on tertiary diarylalkyl boronic esters) or TBAF?3H2O (on tertiary aryldialkyl boronic esters) effect highly efficient protodeboronation of tertiary boronic esters with essentially complete retention of configuration. Furthermore, substituting D2O for H2O provides ready access to deuterium-labeled enantioenriched tertiary alkanes. The methodology has been applied to a short synthesis of the sesquiterpene, (S)-turmerone.
