Hydroboration of Terminal Alkynes Catalyzed by a Mn(I) Alkyl PCP Pincer Complex Following Two Diverging Pathways.

ABSTRACT: A stereo- and regioselective Mn(I)-catalyzed hydroboration of terminal alkynes with pinacolborane (HBPin) is described. The hydroboration reaction is highly Z-selective in the case of aryl alkynes and E-selective in the case of aliphatic alkynes. The reaction requires no additives or solvents and proceeds with a catalyst loading of 1 mol % at 50-70 °C. The most active precatalyst is the bench-stable alkyl Mn(I) complex cis-[Mn(PCP-iPr)(CO)₂(CH₂CH₂CH₃)]. The catalytic process is initiated by the migratory insertion of a CO ligand into the Mn-alkyl bond to yield an acyl intermediate. This species undergoes C-H and B-H bond cleavage of the alkyne (aromatic alkynes) and HBPin (in the case of aliphatic alkynes) formi

SUBMITTER: Zobernig DP 

PROVIDER: S-EPMC11334104 | biostudies-literature | 2024 Aug

REPOSITORIES: biostudies-literature