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
          
       
    
   
      
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         Ethyl (2S )-2-[(diphenylsilyl)oxy]propanoate: 1 H NMR (CD2 Cl2 ): 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).13 C NMR (CD2 Cl2 ): δ = 173.4, 134.9, 130.7, 130.6, 128.3, 128.2, 70.1, 61.2, 20.9, 14.2. HRMS (EI):
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