Enantioselective Alkynylation Reactions to Substituted Benzaldehyde and Salicylaldehyde Derivatives: The Effect of Substituents upon the Efficiency and Enantioselectivity
作者:Elizabeth Tyrrell、Kibur Hunie Tesfa、Alastair Mann、Kuldip Singh
DOI:10.1055/s-2007-966045
日期:——
Asymmetric alkynylation reactions to mono-, di-, and trisubstituted aromatic aldehydes have been accomplished in good yields and with a range of selectivities. For salicylaldehyde derivatives both the yield and the enantioselectivity of the alkynylation reaction appears to depend not only upon the electron-donating/ electron-withdrawing nature of substituents but also upon their position in the ring
单、二和三取代芳香醛的不对称炔基化反应已经以良好的收率和一系列选择性完成。对于水杨醛衍生物,炔基化反应的产率和对映选择性似乎不仅取决于取代基的给电子/吸电子性质,还取决于它们在环中相对于羰基的位置。对于苯甲醛衍生物,这种观察以硝基苯甲醛为例,其中用 3-硝基苯甲醛进行的不对称炔基化以几乎定量的产率和对映选择性发生。相比之下,我们用 4-硝基苯甲醛进行不对称炔基化的尝试失败了。