Stereoselective addition of ethyl 3-morpholino(piperidino)-crotonates to 2-trihalomethyl-3-nitro-2H-chromenes. Synthesis of 4-acetonyl-3-nitrochromans
作者:Vladislav Yu. Korotaev、Igor B. Kutyashev、Alexey Yu. Barkov、Vyacheslav Ya. Sosnovskikh
DOI:10.1007/s10593-015-1718-1
日期:2015.5
Tertiary enamines of acetoacetic ester, obtained with morpholine and piperidine, add to 2-R1-3-nitro-2Н-chromenes (R1 = CF3, CCl3, Ph) via the vinylogue β-methyl group and give the respective cis,trans-2,3,4-trisubstituted chromans, the stereoconfiguration of which was established by X-ray structural analysis. Acidic hydrolysis of these compounds was accompanied by decarboxylation and produced 4-ace
用吗啉和哌啶制得的乙酰乙酸酯的叔烯胺经乙烯基β-甲基加到2-R 1 -3-硝基-2Н-色烯(R 1 = CF 3,CCl 3,Ph)中,得到各自的顺式,反式-2,3,4-三取代的苯并二氢吡喃,其立体构型是通过X射线结构分析确定的。这些化合物的酸性水解伴随脱羧作用,产生具有构型保留的4-丙酮基-3-硝基苯并二氢吡喃。