Zn-Catalyzed Asymmetric Allylation for the Synthesis of Optically Active Allylglycine Derivatives. Regio- and Stereoselective Formal α-Addition of Allylboronates to Hydrazono Esters
作者:Mari Fujita、Takashi Nagano、Uwe Schneider、Tomoaki Hamada、Chikako Ogawa、Shū Kobayashi
DOI:10.1021/ja710627x
日期:2008.3.1
have developed Zn-catalyzed asymmetric allylation of hydrazono esters with allylboronates. The reactions proceeded smoothly in high yields and high stereoselectivities. Remarkably, formal α-addition occurred for α-substituted allylboronates exclusively, and excellent stereoselectivities were observed. This is the first example of catalytic regio- and stereoselective allylations with formal α-addition.
我们开发了锌催化的腙酯与烯丙基硼酸酯的不对称烯丙基化反应。反应以高产率和高立体选择性顺利进行。值得注意的是,α-取代的烯丙基硼酸酯仅发生了正式的 α-加成,并且观察到了优异的立体选择性。这是具有正式α-加成的催化区域和立体选择性烯丙基化的第一个例子。此外,反应是在水性介质中进行的,水的使用是必不可少的。Zn(OH)2 可能是这种不对称烯丙基化反应的催化剂,并且证实了 Zn(OH)2 的催化活性。这也是手性金属氢氧化物催化不对称反应的首例。