The preparation of two new families of hexanuclear rhenium cluster complexes containing benzonitrile and phenylsubstituted tetrazolate ligands is described. Specifically, we report the preparation of a series of cluster complexes with the formula [Re6Se8(PEt3)(5)L](2+) where L = benzonitrile, p-aminobenzonitrile, p-methoxybenzonitrile, p-acetylbenzonitrile, or p-nitrobenzonitrile. All of these complexes undergo a [2 + 3] cycloaddition with N-3(-) to generate the corresponding [Re6Se8(PEt3)(5)(5-(p-X-phenyptetrazol-2-yl)](+) (or [Re6Se8(Ht(3))(5)(2,5-p-X-phenyltetrazolate)(+)) cluster complexes, where X = NH2, OMe, H, COCH3, or NO2. Crystal structure data are reported for three compounds: [Re6Se8(PEt3)(5)(p-acetylbenzonitrile)](BF4)(2) circle MeCN, [Re6Se8(PEt3)(5)(2,5-phenyltetrazolate)](BF4) circle CH2Cl2, and [Re6Se8(PEt3)(5)(2,5-p-aminophenyltetrazolate)] (BF4). Treatment of [Re6Se8(PEt3)(5)(2,5-phenyltetrazolate)RBF4) with HBF4 in CD3CN at 100 degrees C leads to protonation of the tetrazolate ring and formation of [Re6Se8(PEt3)(5)(CD3CN)](2+). Surprisingly, alkylation of the phenyl and methyl tetrazolate complexes ([Re6Se8(PEt3)(5)(2,5-N4CPh)](BF4) and [Re6Se8(PEt3)(5)(1,5-N4CMe)](BF4)) with methyl iodide and benzyl bromide, leads to the formation of mixtures of 1,5- and 2,5-disubstituted tetrazoles.