Reaction of ketenes with<i>N,N</i>-disubstituted α-aminomethyleneketones.<b>XIX</b>. Synthesis of<i>N,N</i>-disubstituted 4-amino-3-phenyl-2<i>H</i>-furo[2,3-<i>h]</i>-1-benzopyran-2-ones (4-amino-3-phenylangelicins). Crystal and molecular structure of 3-Phenylangelicin
作者:Luisa Mosti、Pietro Schenone、Giulia Menozzi、Fernando Sancassan、Francarosa Baccichetti、Franco Benetollo、Gabriella Bombieri
DOI:10.1002/jhet.5570250211
日期:1988.3
phenylchloroketene to N,N-disubstituted 5-aminomethylene-6,7-dihydrobenzo[b]- furan-4(5H)-ones gave the corresponding adducts, namely N,N-disubstituted 4-amino-3-chloro-3,4,5,6-tetra- hydro-3-phenyl-2H-furo[2,3-h]-l-benzopyran-2-ones II, which were dehydrochlorinated with DBN to N,N-disubstituted 4-amino-5,6-dihydro-3-phenyl-2H-furo[2,3-h]-1-benzopyran-2-ones III. Compounds III afforded the title compounds
苯氯乙烯酮的1,4-环加成至N,N-二取代的5-氨基亚甲基-6,7-二氢苯并[ b ]-呋喃-4(5 H)-ones得到相应的加合物,即N,N-二取代的4-氨基- 3-氯-3,4,5,6-四氢-3-苯基-2 H-呋喃并[2,3 - h ] -1-苯并吡喃-2-酮s II,用DBN脱氯化氢成N,N -二取代的4-氨基-5,6-二氢-3-苯基-2 H-呋喃并[2,3 - h ] -1-苯并吡喃-2-酮III。化合物III通过用DDQ脱氢得到标题化合物IV。在环加成步骤中,3-苯基AngelicinV几乎总是形成的,其结构由1 H-nmr迁移试剂数据和X射线晶体结构确定,可能是从II开始,通过二取代氨基的脱氯化氢,脱氢和氢解作用而形成的。在环加成步骤中,或者在大多数情况下,在脱氯化氢步骤中,通过氧化铝色谱法实现V的分离。