Generation of Reactive Species Acyl Lithium and Its Reactions

1.研究了相对未知的羰基阴离子的生成和反应。由芳基异氰化物和t-BuLi生成的β-苯基-2-氮杂乙烯基锂与一氧化碳反应生成~3H-吲哚衍生物，经甲胺猝灭后，产率为42~44%。同样，在苯腈中加成烷基锂得到的β-苯基-1-氮杂乙烯基锂，与一氧化碳和甲醚反应生成1H-异吲哚衍生物，产率为73~81%。1，4-二氮杂丁二烯基阴离子与一氧化碳和甲醚反应生成环状尿素。这些反应代表了二烯基阴离子与一氧化碳以羰基阴离子为中间体的[4+1]环偶联反应。三甲基硅基重氮甲烷在-78ﾟC下与BuLi反应，在-78ﾟC下与一氧化碳反应，然后用三乙基硅基三氟甲磺酸(Et_3SiOTf)淬灭，生成锂基三甲基硅基重氮甲烷，产率为85%。该反应通过从羰基锂中挤出N_2而形成的硅氰酸酯进行。苯基硅酸酯作为酮化试剂。在等摩尔量的Me_3Al存在下，硅烷酸酯与环氧乙烷、苯丙二酸乙酯等亲碳性化合物发生了反应。硅烷酸酯与环氧己烷反应后，经开环烯化反应得到内酯，再经分子内环合反应得到内酯。这些反应是硅烷酸酯被碳亲电体捕获的第一个例子。

1. Generation and reactions of carbonyl anions, relatively unknown species, have been studied. The reaction of beta-phenyl-2-azaethenyllithium, generated from aryl isocyanides and t-BuLi, with carbon monoxide gives 3H-indole derivatives in 42-44% yields after quenching with MeI.Similarly, beta-phenyl-1-azaethenyllithium, obtainable by the addition of alkyllithium to benzonitriles, reacts with carbon monoxide and MeI to afford 1H-isoindole derivatives in 73-81% yields. A 1,4-diazabutadienyl anion gives a cyclic urea on reaction with carbon monoxide and MeI.These reactions represent novel [4+1] cyclocoupling reactions of dienyl anions with carbon monoxide via carbonyl anions as the intermediates.2. The reaction of lithiotrimethylsilyldiazomethane, generated from treatment of trimethylsilyldiazomethane with BuLi at -78ﾟC,with carbon monoxide at -78ﾟC followed by quenching with triethylsilyl trifluoromethanesulfonate (Et_3SiOTf) affords a bissilylketene in 85% yield. The reaction proceeds via a silylynolate which is formed by extrusion of N_2 from the carbonyllithium. The silylynolate act as ketenylation reagent. The silylynolate is found to react with carbon electrophiles such as oxiranes and ethyl benzalmalonate in the presence of equimolar amount of Me_3Al. The treatment of silylynolate with cyclohexene oxide gave a lactone via ring-opeming ketenylation followed by intramolecular cyclization. These reactions are first examples that silylynolate was trapped by carbon electrophiles.