Intra-molecular Diels–Alder reactions of citraconamic acids from furfurylamines and citraconic anhydride: effects of substitution in the furan ring on regioselectivity
作者:Rajappa Murali、H Surya Prakash Rao、Hans W Scheeren
DOI:10.1016/s0040-4020(01)00175-2
日期:2001.4
Regioselectivity in the intra-molecular Diels–Alder (IMDA) reaction of furfurylcitraconamic acids derived from N-benzylfurfurylamines and citraconic anhydride can be controlled by substituents located in the furan ring and by reaction conditions. Reactions conducted under kinetic conditions resulted in cycloaddition products having methyl and aminomethylene substituent in 1,3-relationship whereas under
由呋喃环中的取代基和反应条件可以控制N-苄基糠胺和柠康酸酐衍生的糠基柠檬烯二酸酯分子内Diels-Alder(IMDA)反应中的区域选择性。在动力学条件下进行的反应导致在1,3-关系中具有甲基和氨基亚甲基取代基的环加成产物,而在热力学条件下,除3-甲基硫烷基外,该产物重排成更稳定的环加合物,其中取代基位于1 ,2-关系。可以根据边界轨道相互作用和空间考虑因素来解释产物的形成。