Converting Caffeine to Electronically Different N-Heterocyclic Carbenes with a Hypoxanthine Backbone
作者： Abdelaziz Makhloufi , Walter Frank , Christian Ganter
DOI: 10.1021/OM300836W
关键词: Hypoxanthine 、 Stereochemistry 、 Carbene 、 Adduct 、 Polymer chemistry 、 Structural unit 、 Olefin fiber 、 Yield (chemistry) 、 Chemistry 、 Imidazole 、 Caffeine
摘要: The synthesis of the new mixed amino–amido N-heterocyclic carbene 2, featuring a hypoxanthine structural unit, starting from caffeine via hypoxanthinium precursor 4 is described. NHC 2 forms adducts with group 6 elements, coordinates to L2ClRh fragments (L2 = COD, (CO)2), or dimerizes yield olefin 8. donor properties were evaluated by IR spectroscopic assessment its TEP value (2058 cm–1), which typical for an NHC. Dicarbenes are also easily obtained converting imidazole moieties cation 8 into functions. X-ray structure determinations Rh complex and olefinic dicarbene 13 presented.
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sci-hub.se 参考文章(46)
Rüdiger Walentowski, Hans-Werner Wanzlick, Chemie nucleophiler Carbene, XVI. 2-Thio-coffein und 5-Oxo-7-methylimino-1.4-dimethyl-1.4.5.7-tetrahydro-imidazo[4.5-d][1.3]thiazin Chemische Berichte. ,vol. 102, pp. 3000- 3005 ,(1969) , 10.1002/CBER.19691020915
Jan Schütz, Wolfgang A. Herrmann, Purine-based carbenes at rhodium and iridium Journal of Organometallic Chemistry. ,vol. 689, pp. 2995- 2999 ,(2004) , 10.1016/J.JORGANCHEM.2004.06.037
Joyce A. V. Er, Andrew G. Tennyson, Justin W. Kamplain, Vincent M. Lynch, Christopher W. Bielawski, Synthesis and Study of 5,5′‐Bibenzimidazolylidenes and Their Bimetallic Complexes European Journal of Inorganic Chemistry. ,vol. 2009, pp. 1729- 1738 ,(2009) , 10.1002/EJIC.200801188
Aysegul Kascatan-Nebioglu, Matthew J. Panzner, Jered C. Garrison, Claire A. Tessier, Wiley J. Youngs, Synthesis and Structural Characterization of N-Heterocyclic Carbene Complexes of Silver(I) and Rhodium(I) from Caffeine Organometallics. ,vol. 23, pp. 1928- 1931 ,(2004) , 10.1021/OM030689R
F. Ekkehardt Hahn, Mareike C. Jahnke, Heterocyclic Carbenes: Synthesis and Coordination Chemistry Angewandte Chemie. ,vol. 47, pp. 3122- 3172 ,(2008) , 10.1002/ANIE.200703883
Todd W. Hudnall, Christopher W. Bielawski, An N,N′-Diamidocarbene: Studies in C−H Insertion, Reversible Carbonylation, and Transition-Metal Coordination Chemistry Journal of the American Chemical Society. ,vol. 131, pp. 16039- 16041 ,(2009) , 10.1021/JA907481W
Wofgang Beck, Nikolaus Kottmair, Neue Übergangsmetallkomplexe mit Nuclein-Basen und Nucleosiden Chemische Berichte. ,vol. 109, pp. 970- 993 ,(1976) , 10.1002/CBER.19761090318
Wolfgang A. Herrmann, Jan Schütz, Guido D. Frey, Eberhardt Herdtweck, N-Heterocyclic Carbenes: Synthesis, Structures, and Electronic Ligand Properties Organometallics. ,vol. 25, pp. 2437- 2448 ,(2006) , 10.1021/OM0600801
H.J. Krentzien, M.J. Clarke, H. Taube, Crystal structure of a compound featuring caffeine bound at C8 to ruthenium (III). Bioinorganic Chemistry. ,vol. 4, pp. 143- 151 ,(1975) , 10.1016/S0006-3061(00)81023-6
Christian Radloff, F. Ekkehardt Hahn, Tania Pape, Roland Fröhlich, Supramolecular structures from mono and dimetalated biscarbene ligands Dalton Transactions. pp. 7215- 7222 ,(2009) , 10.1039/B907896G