Hydroboration of Terminal Alkenes and trans-1,2-Diboration of Terminal Alkynes Catalyzed by a Manganese(I) Alkyl Complex.

ABSTRACT: A Mn^I-catalyzed hydroboration of terminal alkenes and a 1,2-diboration of terminal alkynes with pinacolborane (HBPin) is described. For alkenes, anti-Markovnikov hydroboration takes place; for alkynes the reaction proceeds with excellent trans-1,2-selectivity. The most active pre-catalyst is bench-stable alkyl bisphosphine Mn^I complex fac-[Mn(dippe)(CO)₃(CH₂CH₂CH₃)]. The catalytic process is initiated by migratory insertion of a CO ligand into the Mn-alkyl bond to yield an acyl intermediate, which undergoes B-H bond cleavage of HBPin (for alkenes) and rapid C-H bond cleavage (for alkynes), forming the active Mn^I boryl and acetylide catalysts [Mn(dippe)(CO)₂(BPin)] and [Mn(dippe)(CO)₂(C≡CR)],

SUBMITTER: Weber S 

PROVIDER: S-EPMC10947181 | biostudies-literature | 2021 Nov

REPOSITORIES: biostudies-literature