Asymmetric Synthesis of 6-Alkyl- and 6-Arylpiperidin-2-ones. Enantioselective Synthesis of (<i>S</i>)-(+)-Coniine
作者:Stéphane Lebrun、Axel Couture、Eric Deniau、Pierre Grandclaudon
DOI:10.1021/ol070757w
日期:2007.6.1
(1) have been assembled in a highly diastereoselective manner by addition of allyllithium to chiral SAMP hydrazones followed by N-acylation with acryloyl chloride. Substrates 1 undergo ring-closing metathesis to give the cyclic enehydrazides (5) which can be easily converted into virtually enantiopure 6-alkyl- or 6-arylpiperidin-2-ones (7). The versatility of this hydrazone addition-RCM protocol has been
通过将烯丙基锂添加到手性SAMP azo中,然后用丙烯酰氯进行N-酰化,已经以高度非对映选择性的方式组装了各种二烯烃酰肼(1)。底物1进行闭环复分解,得到环状的乙肼(5),其可以容易地转化成实际上对映纯的6-烷基-或6-芳基哌啶-2-酮(7)。通过不饱和杂环5b转化为哌啶生物碱(S)-(+)-i氨酸,可以进一步举例说明这种addition加-RCM方案的多功能性。