Catalytic Asymmetric Iterative/Domino Aldehyde Cross-Aldol Reactions for the Rapid and Flexible Synthesis of 1,3-Polyols
Catalytic Asymmetric Iterative/Domino Aldehyde Cross-Aldol Reactions for the Rapid and Flexible Synthesis of 1,3-Polyols
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DOI：
10.1021/jacs.5b11192
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发表时间：
2015-12-16
影响因子：
15
通讯作者：
Kanai, Motomu
中科院分区：
文献类型：
--
作者：
Lin, Luqing;Yamamoto, Kumiko;Kanai, Motomu
我们在这里报告催化不对称迭代和多米诺交叉醛醇缩合反应之间的醛，赋予了高水平的鲁棒性，灵活性和一般性。Cu（I）-DTBM-SEGPHOS络合物催化受体醛和由供体醛衍生的硼烯醇化物之间的不对称交叉羟醛缩合反应，所述硼烯醇化物通过Ir催化的烯丙氧基硼酸酯的异构化产生。该单元过程可以重复使用醛醇产物，反过来作为受体基板，用于随后的不对称醛醇缩合反应。双羟醛缩合反应的给体醛和立体选择性可以分步灵活切换。此外，不对称的三重和四重羟醛缩合反应是可能的，在一锅中使用适量的供体和胺添加剂，快速延长碳骨架与控制多达八个立体中心。该方法可用于直接合成对映体和非对映体富集的1，3-多元醇。
We report here catalytic asymmetric iterative and domino cross-aldol reactions between aldehydes, endowed with a high level of robustness, flexibility, and generality. A Cu(I)-DTBM-SEGPHOS complex catalyzes an asymmetric cross-aldol reaction between acceptor aldehydes and boron enolates derived from donor aldehydes, which are generated through Ir-catalyzed isomerization of allyloxyboronates. The unit process can be repeated using the aldol products in turn as acceptor substrates for the subsequent asymmetric aldol reaction. The donor aldehydes and stereoselectivity can be flexibly switched in a stepwise manner for the double-aldol reaction. Furthermore, asymmetric triple- and quadruple-aldol reactions are possible in one-pot using the appropriate amounts of donors and amine additives, rapidly elongating the carbon skeleton with controlling up to eight stereocenters. The method should be useful for straightforward synthesis of enantiomerically and diaster-eomerically enriched 1,3-polyols.