초록 |
2-Phenylamino-2-oxazoline chiral auxiliary exhibited excellent level of stereocontrol and stability. Since the success in the mono case, in this study, we wish to investigate the asymmetric alkylation reactions in dipodal case by develop the benzene-based dipodal 2-phenyl amino-2-oxazoline chiral auxiliaries. As expected, the asymmetric benzylation and allylation reactions proceeded well with high stereoselectivity (d.e >99%). However, in case of asymmetric methylation, lower stereocontrol (d.e 70%) was obtained as compared with the mono case. Several cleavage conditions were also examined for the parallel synthesis of several chiral acids, esters and alcohols. |