[Rh(OH)(cod)]₂ (cod = 1,5-Cyclooctadiene): A Highly Efficient Catalyst for 1,4-Hydrosilylation of α,β-Unsaturated Carbonyl Compounds

Abstract

[Rh(OH)(cod)]₂ (cod: 1,5-cyclooctadiene) is found to be a highly efficient catalyst for 1,4-hydrosilylation of α,β-unsaturated carbonyl compounds leading to enolsilanes. The reaction of 2-cyclohexen-1-one with HSiMe(OEt)₂ in the presence of 0.005 mol% of the catalyst without solvent furnishes the corresponding enolsilane in 97% yield at room temperature within 10 min.

[Rh(OH)(cod)]₂ - hydrosilylation - α,β-unsaturated carbonyl compounds - tertiary silanes - enolsilanes

References

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<A NAME="RY06702ST-8">8</A>

The mixture of 2-cyclohexen-1-one (2, 10 mmol) and HSi(OEt)Me₂ (11 mmol) in the presence of [Rh(OH)(cod)]₂ (1 mg, 0.005 mol%) was stirred at room temperature for 10 min under an argon atmosphere. The resulting mixture was subjected to bulb-to-bulb distillation under 0.5 Torr at 55 °C (bath temp) to afford 1.95 g of (1-cyclohexnenyl)ethoxy(dimethyl)silane (97%) as a colorless liquid. ¹H NMR (CDCl₃, 300 MHz) δ 0.18 (s, 6 H), 1.22 (t, J = 7.2 Hz, 3 H), 1.42-1.60 (m, 2 H), 1.61-1.76 (m, 2 H), 1.94-2.14 (m, 4 H), 3.79 (q, J = 7.2 Hz, 2 H), 4.94-4.98 (m, 1 H).