Highly anti-selective dihydroxylation of 1,2-dialkyl substituted (Z)-allylic amines: stereoselective synthesis of a d-ribo-phytosphingosine derivative

Protection of 1,2-dialkyl substituted (Z)-allylic amines with an N,N-diBoc group resulted in an opposite stereoselectivity in the OsO₄-catalyzed dihydroxylation reactions to that of N-Boc-(Z)-allylic amines. A higher anti selectivity (>10:1) was shown in CH₂Cl₂. An efficient stereoselective synthesis of a tetraacetyl derivative of d-ribo-phytosphingosine was reported using the N,N-diBoc-controlled dihydroxylation from Garner’s aldehyde.