Novel Synthesis of Cubane Precursor

Cubane C8H8 is potentially an extremely valuable fuel substitute for the kerosene-based rocket propellant RP-1. The classical Eaton synthesis to yield cubane 1,4-dicarboxylic acid in five steps involves a key photochemical reaction. The steps before and after the critical 2+2 cycloaddition are standardized and readily scalable. However, this steps alone prevents scale-up. We will develop a non-photochemical method for this step. We propose three chemical alternatives: a) radical cation 2+2 cycloaddition via a radical chain process, b) a cobalt catalyzed 2+2 cyclodimerization and c) a nucleophilic addition-cyclization route. Rapid analysis for the success in non-photochemical reaction of the chemical 2+2 is easily done because the properties of the product are already known. Therefore during the six month period of Phase I we will start a screening of many one-electron oxidants for radical cation formation (route a), exhaustively vary reaction parameters for the cobalt catalyzed cyclodimerization, (route b) and investigate a representative number of nucleophiles capable of triggering the intramolecular cyclization in route c.