Enantioselective reductive coupling of 1,3-enynes to glyoxalates mediated by hydrogen:: Asymmetric synthesis of β,γ-unsaturated α-hydroxy esters
Enantioselective reductive coupling of 1,3-enynes to glyoxalates mediated by hydrogen:: Asymmetric synthesis of β,γ-unsaturated α-hydroxy esters
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DOI：
10.1021/ol7015548
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发表时间：
2007-09-13
期刊：
影响因子：
5.2
通讯作者：
Krische, Michael J.
中科院分区：
文献类型：
--
作者：
Hong, Young-Taek;Cho, Chang-Woo;Krische, Michael J.
在乙醛酸乙酯存在下，在环境压力和温度下，使用由（R）-（3，5-Bu-t-4-MeOPh）-MeO-BIPHEP改性的铑催化剂，催化氢化1，3-烯炔1a-8a，导致高度区域选择性和对映选择性的还原偶联，得到相应的β-羟基酯1b-8b。如通过（X）-羟基酯1b的制备所证明的，由二烯侧链体现的末端和内烯烃部分进行选择性操作，一个优于另一个。
Catalytic hydrogenation of 1,3-enynes 1a-8a in the presence of ethyl glyoxalate at ambient pressure and temperature using a rhodium catalyst modified by (R)-(3,5-Bu-t-4-MeOPh)-MeO-BIPHEP results in highly regio- and enantioselective reductive coupling to furnish the corresponding (x-hydroxy esters 1b-8b. As demonstrated by the elaboration of (x-hydroxy ester 1b, the terminal and internal olefin moieties embodied by the diene side chain are subject to selective manipulation, one over the other.