Benzonitrile Oxide Cycloadditions with Exocyclic Methylene Benzothiazepine Dioxides
作者:Sarah J. Ryan、Craig L. Francis、G. Paul Savage
DOI:10.1071/ch13444
日期:——
2]thiazepine 1,1-dioxides underwent 1,3-dipolar cycloaddition with benzonitrile oxide, generated in situ, to give isoxazoline spiro adducts. The cycloadditions were completely regioselective to give the hitherto unreported 3,4-dihydro-2H,4′H-spiro[benzo[f][1,2]thiazepine-5,5′-isoxazole] 1,1-dioxide cycloadduct. Where the N-substituent on the sulfonamide cycloaddition precursor was a 2-substituted arene, the
N-取代的5-亚甲基-2,3,4,5-四氢苯并[ f ] [1,2]噻氮平1,1-二氧化物与苄腈氧化物进行1,3-偶极环加成反应,生成原位生成异恶唑啉螺环加合物。该环加成是完全区域选择性得到迄今未报告的3,4-二氢-2- ħ,4' ħ -螺[苯并[ ˚F ] [1,2]硫氮杂-5,5'-异恶唑] -1,1-二氧化物环加成。在磺酰胺环加成前体上的N-取代基是2-取代的芳烃的情况下,沿着N-芳基键产生的阻转异构作用导致环加成反应中的面部选择性,非对映选择性大于90%。