Tetrazolyl and tetrazolylidene complexes of gold: A synthetic and structural study

Date
2009, 2009
Authors
Gabrielli W.F.
Nogai S.D.
McKenzie J.M.
Cronje S.
Raubenheimer H.G.
Gabrielli W.F.
Nogai S.D.
McKenzie J.M.
Cronje S.
Raubenheimer H.G.
Journal Title
Journal ISSN
Volume Title
Publisher
Abstract
Lithiation of 1-benzyl-1H-tetrazole followed by transmetallation with [AuCl(PPh3)], [Au(C6F5)(tht)] or [AuCl(tht)] (tht = tetrahydrothiophene) and subsequent alkylation afforded cationic 1-benzyl-4-methyl-4,5-dihydro-1H-1,2,3,4-tetrazol-5-ylidene(triphenylphosphine) gold(i), 1, neutral 1-benzyl-4-methyl-4,5-dihydro-1H-1,2,3,4-tetrazol-5- ylidene(pentafluorophenyl)gold(i), 2, and a cationic biscarbene complex, bis(1-benzyl-4-methyl-4,5-dihydro-1H-1,2,3,4-tetrazol-5-ylidene)gold(i), 3. The first complex underwent a homoleptic rearrangement in solution to form 3. Reaction of [Au(N3)PPh3] with the three isocyanides (CH3)2C6H3NC, tBuNC and CyNC, respectively, yielded the corresponding neutral tetrazolyl(phosphine) complexes of gold, [1-(2,6-dimethylphenyl)-1H-tetrazol-5-yl](triphenylphosphine) gold(i), 4, [1-(tert-butyl)-1H-tetrazol-5-yl](triphenylphosphine)gold(i), 6, and [1-(cyclohexyl)-1H-tetrazol-5-yl](triphenylphosphine)gold(i), 7. Alkylation of 4 with methyl triflate on N4 allowed isolation of the crystalline carbene complex 1-(2,6-dimethylphenyl)-4-methyl-4,5-dihydro-1H-1,2,3,4-tetrazol- 5-ylidene)(triphenylphosphine)gold(i), 5. Complex 7 was not isolable in pure form but converts by isocyanide substitution of triphenylphosphine into [1-cyclohexylisocyanide][1-(cyclohexyl)-1H-tetrazol-5-yl]gold(i), 8. From a product mixture of 7 and 8 the transformed molecules [(cyclohexylamino)(ethoxy) carbene](1-cyclohexyl-1H-tetrazol-5-yl)gold(i), 9, and [bis(cyclohexylamino) carbene](1-cyclohexyltetrazol-5-yl)gold(i), 10, co-crystallised spontaneously after a long time at -20 °C. © 2009 The Royal Society of Chemistry and the Centre National de la Recherche Scientifique.
Lithiation of 1-benzyl-1H-tetrazole followed by transmetallation with [AuCl(PPh3)], [Au(C6F5)(tht)] or [AuCl(tht)] (tht = tetrahydrothiophene) and subsequent alkylation afforded cationic 1-benzyl-4-methyl-4,5-dihydro-1H-1,2,3,4-tetrazol-5-ylidene(triphenylphosphine) gold(i), 1, neutral 1-benzyl-4-methyl-4,5-dihydro-1H-1,2,3,4-tetrazol-5- ylidene(pentafluorophenyl)gold(i), 2, and a cationic biscarbene complex, bis(1-benzyl-4-methyl-4,5-dihydro-1H-1,2,3,4-tetrazol-5-ylidene)gold(i), 3. The first complex underwent a homoleptic rearrangement in solution to form 3. Reaction of [Au(N3)PPh3] with the three isocyanides (CH3)2C6H3NC, tBuNC and CyNC, respectively, yielded the corresponding neutral tetrazolyl(phosphine) complexes of gold, [1-(2,6-dimethylphenyl)-1H-tetrazol-5-yl](triphenylphosphine) gold(i), 4, [1-(tert-butyl)-1H-tetrazol-5-yl](triphenylphosphine)gold(i), 6, and [1-(cyclohexyl)-1H-tetrazol-5-yl](triphenylphosphine)gold(i), 7. Alkylation of 4 with methyl triflate on N4 allowed isolation of the crystalline carbene complex 1-(2,6-dimethylphenyl)-4-methyl-4,5-dihydro-1H-1,2,3,4-tetrazol- 5-ylidene)(triphenylphosphine)gold(i), 5. Complex 7 was not isolable in pure form but converts by isocyanide substitution of triphenylphosphine into [1-cyclohexylisocyanide][1-(cyclohexyl)-1H-tetrazol-5-yl]gold(i), 8. From a product mixture of 7 and 8 the transformed molecules [(cyclohexylamino)(ethoxy) carbene](1-cyclohexyl-1H-tetrazol-5-yl)gold(i), 9, and [bis(cyclohexylamino) carbene](1-cyclohexyltetrazol-5-yl)gold(i), 10, co-crystallised spontaneously after a long time at -20 °C. © 2009 The Royal Society of Chemistry and the Centre National de la Recherche Scientifique.
Description
Keywords
carbenoid; cyanide; gold complex; phosphine derivative; trifluoromethanesulfonic acid; unclassified drug; alkylation; article; chemical reaction kinetics; chemical structure; complex formation; crystallography; lithiation; nuclear magnetic resonance spectroscopy; priority journal, carbenoid, cyanide, gold complex, phosphine derivative, trifluoromethanesulfonic acid, unclassified drug, alkylation, article, chemical reaction kinetics, chemical structure, complex formation, crystallography, lithiation, nuclear magnetic resonance spectroscopy, priority journal
Citation
New Journal of Chemistry
33
11
New Journal of Chemistry
33
11