A Mild Synthesis of Unsymmetrical Bis-Alkoxysilanes through Catalyzed Alcoholysis of Hydridosilanes

Abstract

A mild method for the synthesis of unsymmetrical bis-alkoxysilanes has been developed. This method utilizes two readily available catalysts (rhodium acetate dimer and 10% palladium on carbon) that, under neutral aprotic conditions and within reasonable time, give very good yields of the product in two steps without need to isolate intermediates.

Key words

hydridosilanes - alkoxysilanes - alcoholysis - unsymmetrical - silyl ketals

References

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6

Ethyl (2S)-2-[(diphenylsilyl)oxy]propanoate: ¹H NMR (CD₂Cl₂): δ = 7.71-7.67 (m, 4 H), 7.52-7.39 (m, 6 H), 5.53 (s, 1 H), 4.49 (q, J = 6.8 Hz, 1 H), 4.14 (dq, J = 1, 7.1 Hz, 2 H), 1.50 (d, J = 6.8 Hz, 3 H), 1.23 (t, J = 7.1 Hz, 3 H).
¹³C NMR (CD₂Cl₂): δ = 173.4, 134.9, 130.7, 130.6, 128.3, 128.2, 70.1, 61.2, 20.9, 14.2. HRMS (EI): m/z [M - H⁺] calcd for C₁₇H₂₀O₃Si: 299.110348; found: 299.111653.