Undirected, Asymmetric Alkyl Group Functionalizations through Alkane Dehydrogenation.
Feng YuRenqing TaoYiting SuGuixia LiuZheng HuangPublished in: Organic letters (2022)
Direct asymmetric alkyl group functionalizations can potentially convert abundant and inexpensive hydrocarbon feedstocks into value-added chiral fine chemicals. Here, we report a one-pot, dehydrogenation-based strategy for enantioselective formal benzylic C(sp 3 )-H bond borylation. Dehydrogenation of alkylarenes by a pincer-Ir complex produces aryl alkenes via a tandem dehydrogenation/alkene-isomerization catalysis. The subsequent Cu-catalyzed asymmetric alkene hydroboration affords benzylic boronate esters with excellent site- and enantioselectivity. The generality of this strategy has been further demonstrated by asymmetric alkyl group amination.