有机立体化学-Slid-8

例1

OOHPhH+BR2PhOCH2OMeOCH2OMe>90% de

例2

OOOH1) BHB3 . SMe2OHRO2) H2O2 / NaOHR21

例3

OHODIBALOOSR:TolDIBAL / ZnCl2HBuAlROTolOBuSSR:de > 90%TolOHOSR:de > 90%TolClORZnOCCHCl2AlHSTolBuBu22

8.2.3 Aldol 反应

OOHO-OR'H+R\R*R'R*R\

OHOOHOR'R\+R'R\ReRe'HHsyn (erythro)syn (erythro)O+R\ (Si-Re') (Re-Si')R'OLiOHOOHOSiSi'R'R\+R'R\anti (threo)anti (threo) (Si-Si') (Re-Re'

23

手性烯醇盐与非手性醛的Aldol反应

OOBLL2BOTf2R'CHOOROROOHR'ORA (major) L2 R’ A / B

_______________________________ 9-BBN Ph 14 : 1 Et 17 : 1 i-Pr 100 : 1 Dibutyl Ph 40 : 1 Et 50 : 1 i-Pr 100 : 1 Cyclopentyl Ph 75 : 1 Et 100 : 1 i-Pr no reaction

OOH+R'ORB (minor)24