Soluble Catalysts for Improved Pschorr Cyclizations
摘要:
Several improved catalysts for the Pschorr phenanthrene synthesis have been discovered; all are soluble substances which initiate free-radical reactions by electron donation and thereby shorten the reaction time and increase the yield. One technique with K4Fe(CN)(6) in water produced phenanthrene-9-carboxylic acid (6a) in 87% yield, but its application did not extend to substituted examples where the diazonium salt is less soluble in water. A more general procedure with ferrocene in acetone produced not only 6a but also substituted examples 6b-f in yields of 88-94%. A modification which avoids the isolation of diazonium salts was developed for occasional synthetic use.
作者:Edward A. Nodiff、Andrew J. Saggiomo、Keiichi Tanabe、Eugene H. Chen、Masafu Shinbo、Mahesh P. Tyagi、Atsuto Kozuka、Hirotaka Otomasu、Basant L. Verma、David Goff
DOI:10.1021/jm00244a012
日期:1975.10
A series of new 9-phenanthrene aminoalcohols has been prepared in which each compound bears from one to five halogen or halogen-containing moieties. A number of these compounds are extremely active against Plasmodium berghei in the mouse. Some structural requirements for optimal efficacy are considered.