Chemical transformation of protoberberines. XVI. Regioselective introduction of an oxy functionality at the C12-position of the benzo(c)phenanthridine skeleton: A convenient synthesis of macarpine from oxychelirubine.
A novel method for the introduction of an oxy functionality at the C12-position of the benzo[c]phenanthridine skeleton was developed. The method was successfully applied to a biomimetic synthesis of macarpine (3) from oxychelirubine (15), which was easily derived from the corresponding protoberberine (9).
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.
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.
HANAOKA, MIYOJI;CHO, WON JEA;YOSHIDA, SHUJI;FUEKI, TSUKASA;MUKAI, CHISATO, CHEM. AND PHARM. BULL., 38,(1990) N2, C. 3335-3340
作者:HANAOKA, MIYOJI、CHO, WON JEA、YOSHIDA, SHUJI、FUEKI, TSUKASA、MUKAI, CHISATO