Rh2(OAc)4-catalyzed reaction of 2-(2-carbonylvinyl)-3-phenyl-2H-azirines with diazo esters
作者:K. V. Zavyalov、M. S. Novikov、А. F. Khlebnikov、N. V. Rostovskii、G. L. Starova
DOI:10.1134/s1070428017080097
日期:2017.8
Rh2(OAc)4-catalyzed reaction of 2-(2-carbonylvinyl)-3-phenyl-2H-azirines with diazo esters proceeds through an intermediate generation of azirinium ylide suffering a nonstereoselective ring opening to form (3Z)- and (3E)-2-azahexa-1,3,5-trienes. The former depending on configuration of the C5=C6 bond may undergo cyclization either in derivative of 2,3-dihydropyridine, or in pyrrolium ylide that isomerizes
的Rh 2(OAc)4 2-(2- carbonylvinyl)的催化的反应-3-苯基-2- ħ -azirines与通过中间代azirinium叶立德的重氮酯前进患nonstereoselective开环形式(3 Ž) -和(3 E)-2-氮杂六-1,3,5-三烯。前者取决于C 5= C 6键的构型可以在2,3-二氢吡啶的衍生物中或在异构化成1 H-吡咯的衍生物的吡咯叶立德中进行环化。根据DFT计算,在原子C 6处Z取代基的体积增加时,优选形成吡咯由于在空间上负载的1,6-环化的过渡态的不稳定,出现了2-氮杂六烯烯原子C 1上的取代基R 1和R 2的取代基。