CAMPHOR-DERIVED 2-STANNYL-N-BOC-1,3-OXAZOLIDINE - A NEW CHIRAL FORMYLANION EQUIVALENT FOR THE ASYMMETRIC-SYNTHESIS OF 1,2-DIOLS

Optically pure 2-tributylstannyl-N-Boc-1,3-oxazolidine 6, prepared fro m the camphor-derived aminoalcohol 5, was converted to diastereomerica lly pure 2-acyl derivatives 8 in three steps. Reaction of these ketone s with Grignard reagents at -78 degrees C proceeded with high stereose lectivity affording tertiary carbinols which gave 1,2-diols with >96% ee after hydrolysis and reduction of the intermediate a-hydroxy aldehy des. A new deblocking procedure of the t-Boc group is also described.