title: Microwave alkylation of lithium tetrazolate.
abstract: N1-substituted tetrazoles are interesting ligands in transition metal coordination chemistry, especially in the field of spin crossover. Their synthesis is performed in most cases according to the Franke-synthesis, using a primary amine as reagent introducing the substitution pattern. To enhance flexibility in means of substrate scope, we developed a new protocol based on alkylation of lithium tetrazolate with alkyl bromides. The N1-N2 isomerism of the tetrazole during the alkylation was successfully suppressed by use of highly pure lithium tetrazolate and 30 vol.% aqueous ethanol as solvent, leading to pure N1-substituted products. The feasibility of this reaction was demonstrated by a selection of different substrates.
authors.affiliation: Institute of Applied Synthetic Chemistry, TU Wien, Getreidemarkt 9/163-AC, 1060 Vienna, Austria.
authors.forename: Danny
authors.identifier: 0000-0003-3578-1719
authors.initials: D
authors.lastname: Müller
authors.affiliation: Institute of Applied Synthetic Chemistry, TU Wien, Getreidemarkt 9/163-AC, 1060 Vienna, Austria.
authors.forename: Christian
authors.initials: C
authors.lastname: Knoll
authors.affiliation: Institute of Applied Synthetic Chemistry, TU Wien, Getreidemarkt 9/163-AC, 1060 Vienna, Austria.
authors.forename: Peter
authors.initials: P
authors.lastname: Weinberger
keywords: Basicity; Heterocycles; N-Heterocyclic ligands; N1-Tetrazole; Solvent effect; Spin crossover