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We describe the kinetic resolution of α‐silyl‐substituted allylboronate esters via chiral phosphoric acid‐catalyzed chemo‐, diastereo‐ and enantioselective allylboration of aldehydes. This process provides two synthetically versatile enantioenriched compounds, (Z)‐δ‐silyl‐substituted anti‐homoallylic alcohols and α‐silyl‐substituted allylboronate esters, with a selectivity factor up to 328. We propose that the reaction proceeds through a closed chair‐like transition state with the silane moiety occupying a pseudo‐axial position, thus readily resolving α‐silyl‐substituted allylboronate esters. The synthetic utility of the obtained enantioenriched compounds is highlighted by their further transformations to give a diverse set of enantioenriched molecules. [ABSTRACT FROM AUTHOR]

Keywords: Allylboration; Boron; Silicon; Chemoselectivity; Enantioselectivity EN Allylboration Boron Silicon Chemoselectivity Enantioselectivity 2205 2205 1 04/29/21 20210427 NES 210427 The B front cover picture b , provided by Seung Hwan Cho and co-workers, illustrates ( I R i )-TRIP-catalyzed kinetic resolution of -silyl-substituted allylboronate esters through chemo-, diastereo-, and enantioselective allylation of aldehydes. The reaction is proposed to proceed via a chair-like transition state by the double coordination of ( I R i )-TRIP to the C-H bond of aldehydes and the oxygen atom of Bpin group, thus effectively resolving -silyl-substituted allylboronate esters with high enantiomeric ratios. Front Cover Picture: Kinetic Resolution of -Silyl-Substituted Allylboronate Esters via Chemo- and Stereoselective Allylboration of Aldehydes (9/2021). [Extracted from the article]