Studies on the Synthesis of Dibenzoindolizine Derivatives. V. Synthesis of 4', 5' : 4", 5"-Tetramethoxy-3, 4-dihydro-(2', 1' : 1, 2 ; 2", 1" : 5, 6-dibenzoindolizine)

Abstract

Hofmann and Emde degradations had revealed that dehydrolaudanosoline salt, the dehydrogenation product of laudanosoline under specified conditions, is a derivative of the then unknown dibenzoindolizinium salt (II).¹⁾ The correctness of this view is now fully supported by the present synthesis of 4', 5' : 4", 5"-tetramethoxy-3, 4-dihydro-(2', 1' : 1, 2 ; 2", 1" : 5, 6-dibenzoindolizine) (I) which is readily derivable also from dehydrolaudanolinium salt (II). Both these compounds were found to be one and the same by direct comparison.