Synthesis of Benzo[<b><i>c</i></b>]Phenanthridine Alkaloids, Using a Novel Palladium-Phosphine Combination System - Pd(OAc)<sub>2</sub>, DPPP, and Bu<sub>3</sub>P
Total synthesis of several benzo[c]phenanthridinealkaloids was accomplished via an aryl-aryl coupling reaction using a novel Pd reagent prepared from Pd(OAc) 2 , DPPP, and Bu 3 P. This is a versatile method for the coupling reactions of not only aryl triflates and arenes hut also aryl halides and arenes.
使用由 Pd(OAc) 2 、DPPP 和 Bu 3 P 制备的新型 Pd 试剂,通过芳基-芳基偶联反应完成了几种苯并[c]菲啶生物碱的全合成。只有芳基三氟甲磺酸酯和芳烃,还有芳基卤化物和芳烃。
Aryl-Aryl Coupling Reaction Catalyzed by a Palladium Reagent Prepared from Pd(OAc)2 and n-Bu3P
A palladium reagent prepared from Pd (OAc)(2) (0.2 eq) and n-Bu3P (0.6 eq) catalyzed an aryl-aryl coupling reaction. This procedure is effective for coupling reactions of aryl triflate possessing no oxygen groups with arene, and of aryl iodide with arene.
Synthesis of trisphaeridine and norchelerythrine through palladium-catalyzed aryl–aryl coupling reaction
Total syntheses of trisphaeridine (3)
and norchelerythrine (4), fully
aromatized phenanthridine and benzo[c]phenanthridine alkaloids, were
accomplished via the internal arylâaryl coupling reaction of
halo amides protected by a methoxymethyl group with the palladium reagent,
followed by reduction with lithium aluminium hydride and treatment with hydrochloric
acid.