Catalytic Recycling of a Th-H Bond via Single or Double Hydroboration of Inactivated Imines or Nitriles

TY - JOUR

T1 - Catalytic Recycling of a Th-H Bond via Single or Double Hydroboration of Inactivated Imines or Nitriles

AU - Saha, Sayantani

AU - Eisen, Moris S.

N1 - Publisher Copyright: © 2019 American Chemical Society.

PY - 2019/7/5

Y1 - 2019/7/5

N2 - The catalytic activity of the metallacycle thorium amide [(Me3Si)2N]2Th[κ2-(N,C)-CH2Si(CH3)2N(SiMe3)] (Th1) is presented for the selective dihydroboration of nitriles (- CN) with pinacolborane (HBpin). Using significantly low catalyst loading (0.1 mol %), the dihydroborated amines were achieved by the hydroboration of the - CN triple bond attached with aromatic, aliphatic, and heteroatom backbones with high turnover frequency (TOF) as compared to all the reported homogeneous metal catalysts in this reaction. In addition, for aldimines (- C=N -), the hydroboration precatalyst Th2 has been synthesized by the protonolysis of a seven-membered N-heterocyclic iminato ligand (LH) and Th1. The Th2 crystal structure and its performance in the synthesis of hydroborated secondary amine are also here presented. Detailed kinetic studies and thermodynamic and stoichiometric experiments provided us with cumulative evidence supporting the proposed mechanism for the aforementioned reactions.

AB - The catalytic activity of the metallacycle thorium amide [(Me3Si)2N]2Th[κ2-(N,C)-CH2Si(CH3)2N(SiMe3)] (Th1) is presented for the selective dihydroboration of nitriles (- CN) with pinacolborane (HBpin). Using significantly low catalyst loading (0.1 mol %), the dihydroborated amines were achieved by the hydroboration of the - CN triple bond attached with aromatic, aliphatic, and heteroatom backbones with high turnover frequency (TOF) as compared to all the reported homogeneous metal catalysts in this reaction. In addition, for aldimines (- C=N -), the hydroboration precatalyst Th2 has been synthesized by the protonolysis of a seven-membered N-heterocyclic iminato ligand (LH) and Th1. The Th2 crystal structure and its performance in the synthesis of hydroborated secondary amine are also here presented. Detailed kinetic studies and thermodynamic and stoichiometric experiments provided us with cumulative evidence supporting the proposed mechanism for the aforementioned reactions.

KW - hydroboration

KW - imine

KW - nitrile

KW - organoactinide catalyst

KW - thorium

UR - http://www.scopus.com/inward/record.url?scp=85067064237&partnerID=8YFLogxK

U2 - 10.1021/acscatal.9b01399

DO - 10.1021/acscatal.9b01399

M3 - 文章

AN - SCOPUS:85067064237

SN - 2155-5435

VL - 9

SP - 5947

EP - 5956

JO - ACS Catalysis

JF - ACS Catalysis

IS - 7

ER -