作者:Yuji Takashima、Yuki Kaneko、Yuichi Kobayashi
DOI:10.1016/j.tet.2009.10.116
日期:2010.1
A general approach to the (S)- and (R)-isoflavans was invented, and efficiency of the method was demonstrated by the synthesis of (S)-equol ((S)-3), (R)-sativan ((R)-4), and (R)-vestitol ((R)-5). The key step is the allylic substitution of (S)-6a (Ar1=2,4-(MeO)2C6H3) and (R)-6b (Ar1=2,4-(BnO)2C6H3) with copper reagents derived from CuBr·Me2S and Ar2-MgBr (7a, Ar2=4-MeOC6H4; 7b, 2,4-(MeO)2C6H3; 7c,
发明了(S)-和(R)-异黄酮的通用方法,并且该方法的效率通过合成(S)-雌马酚((S)-3),(R)-sativan((R)-4),和(R)-vestitol((R)-5)。关键的步骤是(的烯丙基取代小号) - 6a中(AR 1 = 2,4-(MEO)2 C ^ 6 ħ 3)和(- [R )-图6b(AR 1 = 2,4-(BNO)2 Ç6 H 3)和衍生自CuBr·Me 2 S和Ar 2 -MgBr(7a,Ar 2 = 4-MeOC 6 H 4 ; 7b,2,4-(MeO)2 C 6 H 3 ; 7c,2的铜试剂-momo -4- MeOC 6 ħ 3),家具抗小号ñ 2的产品([R )-图8a和(小号) - 8b中,ç93-97%的手性转移,收率为60-75%。产物的烯烃部分被氧化裂解,然后除去Ar 1部分上的Me和Bn基团。最后,用K 2 CO 3和Mitsunobu试剂对溴化苯酚