Saunthwal Rakesh K, Patel Monika, Danodia Abhinandan K, Verma Akhilesh K
Synthetic Organic Chemistry Laboratory, Department of Chemistry, University of Delhi, Delhi, 110007, India.
Org Biomol Chem. 2015 Feb 7;13(5):1521-30. doi: 10.1039/c4ob02286f.
An efficient palladium-catalyzed tandem approach for the synthesis of highly functionalized tetrahydroquinazolines 4a–q, and 5a–f by the reaction of o-haloanilines 1a–g with acrylates 2a–d and isothiocyanates 3aa–3ah/isocyanates 3ba–3bfvia Heck-conjoined amidation/thioamidation and concomitant chemoselective Michael-addition is described. A competitive experiment showed that isothiocyanates were more reactive than isocyanates. The developed methodology offers an efficient chemoselective process for the synthesis of highly functionalized tetrahydroquinazolines under mild and operationally simple reaction conditions from inexpensive and commercially available starting substrates.
描述了一种高效的钯催化串联方法，通过邻卤代苯胺1a - g与丙烯酸酯2a - d和异硫氰酸酯3aa - 3ah/异氰酸酯3ba - 3bf反应，经由Heck偶联酰胺化/硫代酰胺化以及伴随的化学选择性迈克尔加成反应，合成高度官能化的四氢喹唑啉4a - q和5a - f。一项竞争实验表明，异硫氰酸酯比异氰酸酯更具反应活性。所开发的方法提供了一种高效的化学选择性过程，可在温和且操作简便的反应条件下，从廉价且市售的起始底物合成高度官能化的四氢喹唑啉。
