Chiral Acylsilanes in Organic Synthesis. Part 2). The Role of the Solvent, the Organometallic Reagent, and the Nature of the Substrate for the Diastereoselectivity of 1,2-Additions to Racemic Alkoxymethyl-Substituted Acylsilanes

Article abstract of DOI:10.1002/hlca.19930760507

The role of the solvent, the organometallic reagent, and the nature of the substrate for the diastereoselectivity of 1,2-additions to racemic alkoxymethyl-substituted acylsilanes was investigated with the acylsilanes 1a-d by variation of the reaction parameters.The results obtained in this study support strongly the previously proposed preferred 'chelate-controlled' reaction path followed under several reaction conditions: highest stereoselectivities were obtained with the best chelating substrates reacting with the most Lewis-acidic organometallic reagents in the least donating solvents.It is shown that almost complete stereoselectivity can be obtained using optimal reaction conditions.