Regioselective Palladium(II)-Catalyzed Synthesis of Five- or Seven-Membered Ring Lactones and Five-, Six- or Seven-Membered Ring Lactams by Cyclocarbonylation Methodology
作者:Bassam El Ali、Kazumi Okuro、Giuseppe Vasapollo、Howard Alper
DOI:10.1021/ja953403l
日期:1996.1.1
affording five- or seven-membered ring lactones (bicyclic, tricyclic, and pentacyclic) as the principal products, often in excellent yields. Use of 2-aminostyrenes as reactants and catalytic quantities of palladium acetate and tricyclohexylphosphine, affords five-membered ring lactams in high yield and selectivity. Bicyclic and tricyclic heterocycles containing six-membered ring lactams can be synthesized
2-烯丙基苯酚在催化量的阳离子钯 (II) 络合物 [(PCy3)2Pd(H)(H2O)]+BF4- 或乙酸钯和 1,4-双(二苯基膦) 存在下与一氧化碳和氢气反应丁烷,提供五元或七元环内酯(双环、三环和五环)作为主要产物,通常收率极好。使用 2-氨基苯乙烯作为反应物和催化量的乙酸钯和三环己基膦,以高产率和选择性提供五元环内酰胺。使用催化体系 Pd(OAc)2/PPh3,2-烯丙胺与 CO/H2 反应可以合成含有六元环内酰胺的双环和三环杂环,同时使用 1, 4-双(二苯基膦基)丁烷在后一过程中代替 PPh3 导致以良好的产率形成七元内酰胺苯并氮杂酮。区域化学控制取决于钯催化剂的性质、气体的相对压力和溶剂。