Synthesis of di- and cis -triaryl-3a,4,5,6-tetrahydroimidazo[1,5- b ]isoxazoles and their ring-opening reactions
作者:Necdet Coşkun、Fatma Tirli Tat、Özden Özel Güven
DOI:10.1016/s0040-4020(01)00184-3
日期:2001.4
diastereoselective cycloaddition with dimethyl acetylenedicarboxylate 2 to give 3a,4,5,6-tetrahydroimidazo[1,5-b]isoxazoles 3. Thermally and base induced ring-opening reactions of compounds 3 were demonstrated. cis-6-Phenyl substituted adducts 3d,e undergo ring opening with secondary but not with tertiary amines. The same adducts undergo regio- and diastereoselective Michael addition with sodium methoxide to give
的Δ 3 -咪唑啉-3-氧化物1经历非对映选择性环加成与乙炔二2,得到3α,4,5,6-四氢咪唑并[1,5- b ]异恶唑3。证明了化合物3的热和碱诱导的开环反应。顺式-6-苯基取代的加合物3d,e与仲胺而不是叔胺一起开环。相同的加合物与甲醇钠一起进行区域和非对映选择性迈克尔加成反应,得到2-甲氧基-3a,5,6-三苯基-六氢-咪唑并[1,5 - b ]异恶唑-2,3-二羧酸二甲酯6。