Benzene → Tridecane

Participants

Reaction Steps

A preferred preparation of the compounds of formula I wherein Y is NH and R2 is hydrogen is to react 1,4,7,10-tetraazacyclododecane, known in the art, with dimethylformamidedimethylacetal in the presence of benzene to yield 1,4,7,10-tetraazatricyclo [5.5.1.0]tridecane. This "tricyclic" compound is reacted with an ethanol/water mixture to yield 1-formyl-1,4,7,10-tetraazacyclododecane. This formyl compound is then reacted with t-butyl bromoacetate to yield 1-formyl, 4,7, 10-triscarboxy-methyl-1,4,7,10-tetraazacyclododecane, tris-t-butylester. Finally, the ester groups are removed in the presence of strong acid, such as sulfuric acid, to yield a compound of formula I wherein Y is NH and R2 is hydrogen.

Provenance & Evidence