Palladium-catalyzed asymmetric synthesis of allylic alcohols from unsymmetrical and symmetrical racemic allylic carbonates featuring C–O-bond formation and dynamic kinetic resolution
作者:Hans-Joachim Gais、Oleg Bondarev、Ralf Hetzer
DOI:10.1016/j.tetlet.2005.07.044
日期:2005.9
Described is the asymmetric synthesis of the allylic alcohols 11 (85% ee), 15 (99% ee), 17 (93% ee), 19 (61% ee), and 21 (69% ee) through a Pd-catalyzed reaction of the unsymmetrical carbonates rac-10, rac-12, rac-14, rac-16, rac-18, and rac-20, respectively, with KHCO3 and H2O in the presence of bisphosphane 6. Similarly the allylic alcohols 23 (99% ee) and 25 (97% ee) have been obtained from the symmetrical
描述了通过Pd催化反应不对称合成烯丙醇11(85%ee),15(99%ee),17(93%ee),19(61%ee)和21(ee%)在双膦6存在下用KHCO 3和H 2 O分别分离不对称碳酸盐rac - 10,rac - 12,rac - 14,rac - 16,rac - 18和rac - 20。。类似地,分别从对称的碳酸盐rac - 22和rac - 24获得了烯丙醇23(ee为99%)和25(ee为97%)。所述的反应内消旋-biscarbonate 26用H 2 O和钯(0)/ 6醇,得到27(96%EE),将其转化到PG构建块32。不饱和bisphosphane 33在醇的合成显示36,37,和39类似的高选择性为6。醇的形成11,15和17涉及一种有效的动态动力学拆分。