Palladium-Catalyzed Cross-Coupling of 2,5-Cyclohexadienyl-Substituted Aryl or Vinylic Iodides and Carbon or Heteroatom Nucleophiles
作者:Richard C. Larock、Xiaojun Han
DOI:10.1021/jo981876f
日期:1999.3.1
most cases, this process is highly diastereoselective. The reaction is believed to proceed via (1) oxidative addition of the aryl or vinylic iodide to Pd(0), (2) organopalladium addition to one of the carbon-carbon double bonds, (3) palladium migration along the carbon chain on the same face of the ring to form a pi-allylpalladium intermediate, and (4) nucleophilic displacement of the palladium.
2,5-环己二烯基取代的芳基或乙烯基碘已与亲核碳(丙二酸二乙酯和2-甲基-1,3-环己二酮),亲核氮(吗啉,邻苯二甲酰亚胺钾,N-苄基甲苯磺酰胺,二叔丁基)反应亚氨基二羧酸盐,叠氮化锂和苯胺),硫亲核试剂(苯磺酸钠)和氧亲核试剂(乙酸锂和苯酚),可以很好地提供环化产物和随后的交叉偶联产物,收率很好。在大多数情况下,此过程是高度非对映选择性的。据信该反应是通过(1)芳基或乙烯基碘的氧化加成到Pd(0)上的,(2)有机钯加成到碳-碳双键之一上的,(3)钯沿着碳原子上的碳链迁移的。环的同一面形成pi-allpalladium中间体,