Department of Chemistry, Middle Tennessee State University , Murfreesboro, Tennessee 37132, United States.
Rigaku Americas , The Woodlands, Texas 77381, United States.
J Org Chem. 2017 May 5;82(9):4924-4929. doi: 10.1021/acs.joc.7b00284. Epub 2017 Apr 17.
We report here the first systematic study of nickel-catalyzed decarbonylation of aromatic aldehydes under relatively mild conditions. Aldehydes with electron donating groups at para and ortho positions are generally successful with our method. For aldehydes with electron-withdrawing groups, significantly higher yields were achieved for ortho-substituted substrates than para ones, probably due to the effects of steric hindrance or electron donors at the ortho position to suppress the Tishchenko reaction, an undesirable side reaction toward homocoupled esters.
我们在此报告了首例在相对温和条件下镍催化芳香醛脱羰反应的系统研究。带有供电子基团的邻位和对位取代的醛通常可以通过我们的方法获得成功。对于带有吸电子基团的醛，邻位取代底物的产率明显高于对位取代底物，这可能是由于邻位的空间位阻或供电子基团对抑制 Tishchenko 反应（一种不利于偶联酯形成的副反应）的影响所致。
