Abstract
The anion of N-phenylsydnone, which can be generated on treatment of N-phenylsydnone with cyanomethyllithium without decomposition, can be represented as tripolar zwitterionic and as anionic N-heterocyclic carbene resonance forms. Its palladium complex was prepared from 4-bromo-3-phenylsydnone and tetrakis(triphenylphosphine)palladium and proved to be active as catalyst in Suzuki-Miyaura reactions. Thus, 2,5-dibromo-3,4-dinitrothiophene was effectively converted into 2,5-diaryl-3,4-dinitrothiophenes with 1-naphthyl, (4-trifluoromethoxy)phenyl, [4-(methylsulfanyl)phenyl], and biphenyl-4-yl boronic acid. 3-(Phenanthren-9-yl)quinoline was prepared by Suzuki-Miyaura reaction starting from 3-bromoquinoline. 1-Chloro-2,4-dinitrobenzene cross-coupled with phenyl boronic acid, 1-naphthyl boronic acid, 9-phenanthryl boronic acid. 4-Bromobenzylic alcohol gave (4-isopropylphenyl)methanol on sydnone-palladium complex-catalyzed reaction with isopropyl boronic acid.
摘要:N-苯基苯并并酮的阴离子可通过用氰甲基锂处理N-苯基苯并并酮而不分解生成,可表示为三极离子和带负电荷的N-杂环卡宾共振形式。其钯配合物是由4-溴-3-苯基苯并并酮和四(三苯基膦)钯制备而成,并证明在Suzuki-Miyaura反应中作为催化剂具有活性。因此,2,5-二溴-3,4-二硝基噻吩有效地转化为具有1-萘基、[4-(三氟甲氧基)苯基]、[4-(甲硫基)苯基]和联苯基-4-基硼酸的2,5-二芳基-3,4-二硝基噻吩。通过Suzuki-Miyaura反应从3-溴喹啉开始制备了3-(苯并并-9-基)喹啉。1-氯-2,4-二硝基苯与苯基硼酸、1-萘基硼酸、9-苯并基硼酸发生交叉偶联。4-溴苄醇与异丙基硼酸在苯并并酮-钯配合物催化反应中生成(4-异丙基苯基)甲醇。