作者:Gary M. Karp
DOI:10.1021/jo9908400
日期:1999.10.1
gives the expected N-methyl analogue 9. When a tandem one-pot cyclization/alkylation is carried out from 6b in the presence of excess base, the sole isolable product obtained is the phosphonate 13, presumably via ethanolysis of a transiently formed 9. Carrying out the tandem cyclization/alkylation in the absence of excess base, however, affords only 9. Thionation of 7 with Lawesson's reagent occurs at either
总体上良好地完成了新型1,4,2-苯并二氮杂磷平-5-酮2-氧化物环体系的短而有效的合成,该体系是1,4-苯并二氮杂-2,5-二酮体系的膦酰胺等排体。让。关键步骤是碱诱导的(2-氨基苯甲酰胺基)甲基膦酸酯6a-c环化为1,4,2-苯并二氮杂磷酰基-5-酮2-氧化物7a-c。7b与碘甲烷烷基化得到预期的N-甲基类似物9。当在过量碱的存在下从6b进行串联一锅环化/烷基化反应时,唯一可分离的产物是膦酸酯13,大概是通过乙醇的乙醇化一个短暂形成的9.在没有过量碱的情况下进行串联环化/烷基化,但是,仅得到9.用Lawesson'