A Versatile NHC-Parent Silyliumylidene Cation for Catalytic Chemo- and Regioselective Hydroboration

Research output: Journal Publications and Reviews (RGC: 21, 22, 62)21_Publication in refereed journal

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Author(s)

  • Bi-Xiang Leong
  • Jiawen Lee
  • Yan Li
  • Ming-Chung Yang
  • Ming-Der Su
  • Cheuk-Wai So

Related Research Unit(s)

Detail(s)

Original languageEnglish
Pages (from-to)17629-17636
Journal / PublicationJournal of the American Chemical Society
Volume141
Issue number44
Online published10 Oct 2019
Publication statusPublished - 6 Nov 2019

Abstract

This study describes the first use of a silicon(II) complex, NHC-parent silyliumylidene cation complex [(IMe)2SiH]I (1, IMe = :C{N(Me)C(Me)}2) as a versatile catalyst in organic synthesis. Complex 1 (loading: 10 mol %) was shown to act as an efficient catalyst (reaction time: 0.08 h, yield: 94%, TOF = 113.2 h-1; reaction time: 0.17 h, yield: 98%, TOF = 58.7 h-1) for the selective reduction of CO2 with pinacolborane (HBpin) to form the primarily reduced formoxyborane [pinBOC(=O)H]. The activity is better than the currently available base-metal catalysts used for this reaction. It also catalyzed the chemo- and regioselective hydroboration of carbonyl compounds and pyridine derivatives to form borate esters and N-boryl-1,4-dihydropyridine derivatives with quantitative conversions, respectively. Mechanistic studies show that the silicon(II) center in complex 1 activated the substrates and then mediated the catalytic hydroboration. In addition, complex 1 was slightly converted into the NHC-borylsilyliumylidene complex [(IMe)2SiBpin]I (3) in the catalysis, which was also able to mediate the catalytic hydroboration.

Research Area(s)

  • N-HETEROCYCLIC SILYLENE, STABLE SILYLENE, BOND ACTIVATION, CARBON-DIOXIDE, REACTIVITY, REDUCTION, HYDRIDE, COMPLEXES, ELEMENTS, KETONES

Citation Format(s)

A Versatile NHC-Parent Silyliumylidene Cation for Catalytic Chemo- and Regioselective Hydroboration. / Leong, Bi-Xiang; Lee, Jiawen; Li, Yan; Yang, Ming-Chung; Siu, Chi-Kit; Su, Ming-Der; So, Cheuk-Wai.

In: Journal of the American Chemical Society, Vol. 141, No. 44, 06.11.2019, p. 17629-17636.

Research output: Journal Publications and Reviews (RGC: 21, 22, 62)21_Publication in refereed journal