TY - JOUR
T1 - Highly diastereoselective allylation and reduction of chiral camphor-derived α-ketoamides
AU - Kulkarni, Neelesh A.
AU - Wang, Shy Guey
AU - Lee, Li Chen
AU - Tsai, Huei Ru
AU - Venkatesham, Uppala
AU - Chen, Kwunmin
PY - 2006/2/6
Y1 - 2006/2/6
N2 - The diastereoselective allylation and reduction of camphor-derived α-ketoamides to give optically enriched α-hydroxyl amides with high to excellent stereoselectivities are described. Allylation was carried out using allyltributylstannane in the presence of a stoichiometric amount of a Lewis acid to afford the desired homoallylic alcohols in relatively high chemical yields (up to 98%) and stereoselectivities (up to 98% de). Diastereoselective reductions were performed with the relatively bulky hydride K-Selectride at -78°C to give the corresponding α-hydroxy amides in excellent chemical yields (up to 98%) and stereoselectivities (up to 98% de). The absolute configuration of the new stereogenic center of the major diastereomer was established by X-ray crystallographic analysis. Finally, stereochemical induction and the Lewis acid dependent reversal of stereoselectivity is described.
AB - The diastereoselective allylation and reduction of camphor-derived α-ketoamides to give optically enriched α-hydroxyl amides with high to excellent stereoselectivities are described. Allylation was carried out using allyltributylstannane in the presence of a stoichiometric amount of a Lewis acid to afford the desired homoallylic alcohols in relatively high chemical yields (up to 98%) and stereoselectivities (up to 98% de). Diastereoselective reductions were performed with the relatively bulky hydride K-Selectride at -78°C to give the corresponding α-hydroxy amides in excellent chemical yields (up to 98%) and stereoselectivities (up to 98% de). The absolute configuration of the new stereogenic center of the major diastereomer was established by X-ray crystallographic analysis. Finally, stereochemical induction and the Lewis acid dependent reversal of stereoselectivity is described.
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U2 - 10.1016/j.tetasy.2006.01.011
DO - 10.1016/j.tetasy.2006.01.011
M3 - Article
AN - SCOPUS:33644698364
VL - 17
SP - 336
EP - 346
JO - Tetrahedron Asymmetry
JF - Tetrahedron Asymmetry
SN - 0957-4166
IS - 3
ER -