International Research Experience for Undergraduates

Angelique Blackburn

2002 Participant


Synthesis of N,N-Dimethyl-Isoquinoleinium

An interest in recent years has been the formation of heterocyclic nitrogen complexes via organometallic chemistry. It has been proposed that these complexes can be formed by substituting on a metal of a previously formed cyclopalladated complex (1). Insertion of an allene into one of these complexes can result in the formation of indolinium, quinolizinium, and benzazepizinium derivatives. The primary concern is formation of an isoquinoleinium. A method for the formation of N,N-dimethyl-isoquinoleinium will be devised. This same method can then be used to synthesize a more complex berberinium. Berberiniums are of interest due to their pharmacological properties (1).

The aim is to make an insertion of an allene into the cyclopalladated complex and then to transform the complex to the desired compound, by ozonolysis into a ketone and its subsequent reduction. Four basic steps will be used to form N,N-dimethyl-isoquinoleinium. The N,N-dimethylbenzylamine (A) will first be complexed with palladium using the reaction previously described (B). Dimethylallene (C) will then be inserted to form the intermediate (D). This intermediate will be oxidized (E), then reduced, to yield the final product (F).