PUMA publications for /user/b_schwederski/copper%20modelhttps://puma.ub.uni-stuttgart.de/user/b_schwederski/copper%20modelPUMA RSS feed for /user/b_schwederski/copper%20model2024-03-28T15:18:34+01:00Sensitive valence tautomer equilibrium of paramagnetic complexes (L)Cun+(Qn-) (n = 1 or 2; Q = quinones) related to amine oxidase enzymeshttps://puma.ub.uni-stuttgart.de/bibtex/2f4bfbce5123442f521dad175cbcf31ca/b_schwederskib_schwederski2019-07-15T13:41:23+02:00amine benzoquinone catecholate complex complex;semiquinone copper isomerism isomerism;catecholate isomerism;crystal model oxidase prepn structure structure;copper triazacyclononane valence <span data-person-type="author" class="authorEditorList "><span><span itemtype="http://schema.org/Person" itemscope="itemscope" itemprop="author"><a title="Jochen Rall" itemprop="url" href="/person/15700a7f5f5061539e8617ee19b762fff/author/0"><span itemprop="name">J. Rall</span></a></span>, </span><span><span itemtype="http://schema.org/Person" itemscope="itemscope" itemprop="author"><a title="Matthias Wanner" itemprop="url" href="/person/15700a7f5f5061539e8617ee19b762fff/author/1"><span itemprop="name">M. Wanner</span></a></span>, </span><span><span itemtype="http://schema.org/Person" itemscope="itemscope" itemprop="author"><a title="Markus Albrecht" itemprop="url" href="/person/15700a7f5f5061539e8617ee19b762fff/author/2"><span itemprop="name">M. Albrecht</span></a></span>, </span><span><span itemtype="http://schema.org/Person" itemscope="itemscope" itemprop="author"><a title="Fridmann M. Hornung" itemprop="url" href="/person/15700a7f5f5061539e8617ee19b762fff/author/3"><span itemprop="name">F. Hornung</span></a></span>, </span> and <span><span itemtype="http://schema.org/Person" itemscope="itemscope" itemprop="author"><a title="Wolfgang. Kaim" itemprop="url" href="/person/15700a7f5f5061539e8617ee19b762fff/author/4"><span itemprop="name">W. Kaim</span></a></span></span>. </span><span class="additional-entrytype-information"><span itemtype="http://schema.org/PublicationIssue" itemscope="itemscope" itemprop="isPartOf"><em><span itemprop="journal">Chemistry - A European Journal</span>, </em> <em><span itemtype="http://schema.org/PublicationVolume" itemscope="itemscope" itemprop="isPartOf"><span itemprop="volumeNumber">5 </span></span>(<span itemprop="issueNumber">10</span>):
<span itemprop="pagination">2802--2809</span></em> </span>(<em><span>1999<meta content="1999" itemprop="datePublished"/></span></em>)</span>Mon Jul 15 13:41:23 CEST 2019Chemistry - A European Journal102802--2809Sensitive valence tautomer equilibrium of paramagnetic complexes [(L)Cun+(Qn-)] (n = 1 or 2; Q = quinones) related to amine oxidase enzymes51999amine benzoquinone catecholate complex complex;semiquinone copper isomerism isomerism;catecholate isomerism;crystal model oxidase prepn structure structure;copper triazacyclononane valence Using the bidentate ligand L = 1-methyl-2-(alkylthiomethyl)-1H-benzimidazole with mixed imidazole-N and thioether-S functions, the authors were able to observe valence tautomer (redox isomer) equil. [(L)CuII(Q-II)] .dblharw. [(L)Cu1(Q-1)] by EPR spectroscopy (Q = alkyl-substituted 3-tert-butyl-o-benzoquinones). These systems are the 1st to show such behavior outside amine oxidase enzymes, where the intramol. electron transfer is essential for the activation of O2 by copper(I). In contrast, coligands contg. exclusively thioether functions yield only copper(I)/o-semiquinone radical complexes, while the use of 1,4,7-trimethyl-1,4,7-triazacyclononane (Me3TACN) gave a structurally and spectroelectrochem. characterized copper(II)/catecholate complex [(Me3TACN)Cu(Q3)] (Q3 = 3,5-di-tert-butylcatecholate) in which the square-pyramidally coordinated metal forms one weak and two strong bonds to the three nitrogen donor atoms. Most remarkably, rather small modifications of the quinone shift the valence tautomer equil.: the use of slightly more electron-rich methoxy-rather than alkyl-substituted 3-tert-butyl-o-benzoquinones and L resulted in semiquinone/copper(I) formation exclusively. [on SciFinder(R)]Aggregation control of copper(I) thiolates through substituent size and ancillary chelate ligands: Closely related mono-, di-, tri- and tetranuclear complexeshttps://puma.ub.uni-stuttgart.de/bibtex/291d93a992dab69660e6017ac253b38b2/b_schwederskib_schwederski2019-07-15T13:41:23+02:00blue complex complex;protein copper model phenanthroline prepn structure structure;crystal thiolate <span data-person-type="author" class="authorEditorList "><span><span itemtype="http://schema.org/Person" itemscope="itemscope" itemprop="author"><a title="Andreas F. Stange" itemprop="url" href="/person/1718343c32ac3ccd2a4cdec3a5671d3d7/author/0"><span itemprop="name">A. Stange</span></a></span>, </span><span><span itemtype="http://schema.org/Person" itemscope="itemscope" itemprop="author"><a title="Axel Klein" itemprop="url" href="/person/1718343c32ac3ccd2a4cdec3a5671d3d7/author/1"><span itemprop="name">A. Klein</span></a></span>, </span><span><span itemtype="http://schema.org/Person" itemscope="itemscope" itemprop="author"><a title="Karl-Wilhelm Klinkhammer" itemprop="url" href="/person/1718343c32ac3ccd2a4cdec3a5671d3d7/author/2"><span itemprop="name">K. Klinkhammer</span></a></span>, </span> and <span><span itemtype="http://schema.org/Person" itemscope="itemscope" itemprop="author"><a title="Wolfgang. Kaim" itemprop="url" href="/person/1718343c32ac3ccd2a4cdec3a5671d3d7/author/3"><span itemprop="name">W. Kaim</span></a></span></span>. </span><span class="additional-entrytype-information"><span itemtype="http://schema.org/PublicationIssue" itemscope="itemscope" itemprop="isPartOf"><em><span itemprop="journal">Inorganica Chimica Acta</span>, </em> <em><span itemtype="http://schema.org/PublicationVolume" itemscope="itemscope" itemprop="isPartOf"><span itemprop="volumeNumber">324 </span></span>(<span itemprop="issueNumber">1,2</span>):
<span itemprop="pagination">336--341</span></em> </span>(<em><span>2001<meta content="2001" itemprop="datePublished"/></span></em>)</span>Mon Jul 15 13:41:23 CEST 2019Inorganica Chimica Acta1,2336--341Aggregation control of copper(I) thiolates through substituent size and ancillary chelate ligands: Closely related mono-, di-, tri- and tetranuclear complexes3242001blue complex complex;protein copper model phenanthroline prepn structure structure;crystal thiolate The choice of thiolates and of ancillary N chelate ligands N-N dets. the aggregation state of Cu(I) thiolate compds. [(RS)xCuy(N-N)z]k. Starting from electrogenerated [(RS)Cu]n, the species obtained and structurally characterized include (i) mononuclear (RS)Cu(Me4phen), Me4phen = 3,4,7,8-tetramethyl-1,10-phenanthroline, with 2,6-diorganophenylthiolates RS-, (ii) dinuclear [(\textgreek{m}-RS)Cu(Me2phen)]2, Me2phen = 2,9-dimethyl-1,10-phenanthroline, with R = Ph or o-tolyl, (iii) trinuclear (\textgreek{m}-RS)3Cu3(Me4phen)2 with R = mesityl, (iv) tetranuclear (\textgreek{m}-RS)4Cu4(bpy)2 with R = 2,4,6-i-Pr3C6H2, and (v) the tetranuclear dianion [(\textgreek{m}-RS)6Cu4]2- where the added chelate ligand N-N = bis(2-imidazolyl)ketone occurs in the [(N N)2Cu]+ counterions. The new trinuclear (\textgreek{m}-MesS)3Cu3(Me4phen)2 exhibits an unsym. Cu3S3 six-membered ring in which the dicoordinate Cu(I) center has a nearly linear configuration (angle S-Cu-S 173.93(13)°). Both tetracoordinate Cu(I) atom sites exhibit a characteristic distortion from a tetrahedral towards a trigonal pyramidal CuN2S2 arrangement which is reminiscent of the geometry obsd. for the rhombic variants of type 1 Cu centers in blue Cu proteins. [on SciFinder(R)]Synthetic and spectroscopic approaches to the copper/quinone-coupled center in amine oxidases: Bioinorg. Chemhttps://puma.ub.uni-stuttgart.de/bibtex/2d5878964f65d884a81264059d7f2b2a2/b_schwederskib_schwederski2019-07-15T13:41:23+02:00amine benzoquinone copper methylthiomethylbenzimidazole methylthiomethylbenzimidazole;copper model oxidase prepn quinone tautomerism;review valence <span data-person-type="editor" class="authorEditorList "><span><span itemtype="http://schema.org/Person" itemscope="itemscope" itemprop="editor"><a title="Jochen Rall" itemprop="url" href="/person/16de770c5601250d356e03c5c85e901ca/editor/0"><span itemprop="name">J. Rall</span></a></span>, </span><span><span itemtype="http://schema.org/Person" itemscope="itemscope" itemprop="editor"><a title="Eberhard Waldhor" itemprop="url" href="/person/16de770c5601250d356e03c5c85e901ca/editor/1"><span itemprop="name">E. Waldhor</span></a></span>, </span><span><span itemtype="http://schema.org/Person" itemscope="itemscope" itemprop="editor"><a title="Brigitte Schwederski" itemprop="url" href="/person/16de770c5601250d356e03c5c85e901ca/editor/2"><span itemprop="name">B. Schwederski</span></a></span>, </span><span><span itemtype="http://schema.org/Person" itemscope="itemscope" itemprop="editor"><a title="Manuela Schwach" itemprop="url" href="/person/16de770c5601250d356e03c5c85e901ca/editor/3"><span itemprop="name">M. Schwach</span></a></span>, </span><span><span itemtype="http://schema.org/Person" itemscope="itemscope" itemprop="editor"><a title="Stephan Kohlmann" itemprop="url" href="/person/16de770c5601250d356e03c5c85e901ca/editor/4"><span itemprop="name">S. Kohlmann</span></a></span>, </span> and <span><span itemtype="http://schema.org/Person" itemscope="itemscope" itemprop="editor"><a title="Wolfgang. Kaim" itemprop="url" href="/person/16de770c5601250d356e03c5c85e901ca/editor/5"><span itemprop="name">W. Kaim</span></a></span></span> (Eds.) </span><span class="additional-entrytype-information"><em><span itemprop="publisher">Wiley-VCH Verlag GmbH</span>, </em>(<em><span>1997<meta content="1997" itemprop="datePublished"/></span></em>)</span>Mon Jul 15 13:41:23 CEST 2019Synthetic and spectroscopic approaches to the copper/quinone-coupled center in amine oxidases: Bioinorg. Chem1997amine benzoquinone copper methylthiomethylbenzimidazole methylthiomethylbenzimidazole;copper model oxidase prepn quinone tautomerism;review valence The interaction between the metal and the potentially o- or p-quinonoid topaquinone (TPQ) ligand in the active site of Cu-dependent amine oxidases was approached using (Qn-)Cun+(L), Q = 3,5-di-tert-butyl-o-benzoquinone and L = 1-alkyl-2-(methylthiomethyl)-1H-benzimidazole, as a first model system for the enzymically relevant and EPR-detectable valence tautomerism (n = 1 or 2). The data are preceded by a review of model systems related to the function and coupling of Cu metal and the org. cofactor in copper-dependent amine oxidases, including the use of 2,4,5-trihydroxytoluene as a model for TPQ. [on SciFinder(R)]Paramagnetic copper(I) dimershttps://puma.ub.uni-stuttgart.de/bibtex/2ba0f2947ced7d1b23841b493e8d4663c/b_schwederskib_schwederski2019-07-15T13:41:23+02:001 bispyridyl cofactor complex;methoxatin copper dicopper dinuclear model paramagnetic paramagnetic;tetrazine phenanthrolinedione;phenanthrolinedione <span data-person-type="author" class="authorEditorList "><span><span itemtype="http://schema.org/Person" itemscope="itemscope" itemprop="author"><a title="Wolfgang Kaim" itemprop="url" href="/person/18ff94642c1084050bf244830c1771687/author/0"><span itemprop="name">W. Kaim</span></a></span>, </span> and <span><span itemtype="http://schema.org/Person" itemscope="itemscope" itemprop="author"><a title="Stephan. Kohlmann" itemprop="url" href="/person/18ff94642c1084050bf244830c1771687/author/1"><span itemprop="name">S. Kohlmann</span></a></span></span>. </span><span class="additional-entrytype-information"><span itemtype="http://schema.org/PublicationIssue" itemscope="itemscope" itemprop="isPartOf"><em><span itemprop="journal">Inorganic Chemistry</span>, </em> <em><span itemtype="http://schema.org/PublicationVolume" itemscope="itemscope" itemprop="isPartOf"><span itemprop="volumeNumber">26 </span></span>(<span itemprop="issueNumber">10</span>):
<span itemprop="pagination">1469--1470</span></em> </span>(<em><span>1987<meta content="1987" itemprop="datePublished"/></span></em>)</span>Mon Jul 15 13:41:23 CEST 2019Inorganic Chemistry101469--1470Paramagnetic copper(I) dimers2619871 bispyridyl cofactor complex;methoxatin copper dicopper dinuclear model paramagnetic paramagnetic;tetrazine phenanthrolinedione;phenanthrolinedione The first paramagnetic Cu(I) dimers [L2Cu(\textgreek{m}-L1)CuL2]+.bul. (L = PPh3, L2 = Ph2PCH2CH2PPh2, 1,5-cyclooctadiene) were obtained as stable species from the reactions of Cu(I) reagents with electron-deficient binucleating ligands L1 = 3,6-bis(2-pyridyl)-1,2,4,5-tetrazine (I) and 4,7-phenanthroline-5,6-dione (II) under reducing conditions. ESR spectroscopy reveals that the unpaired electron resides mainly in the \textgreek{p}* orbital of the bridging ligand L1 whereas a small amt. of spin d. is hyperconjugatively transferred to the L2Cu(I) fragments. Complexes of I may be regarded as models for the metal-to-ligand charge-transfer excited state in (\textgreek{a}-diimine)/Cu(I) species whereas the \textgreek{a}-amino-o-quinone ligand II can serve as model for the dehydrogenase and amine oxidase cofactor methoxatin. [on SciFinder(R)]Copper(I) complexes with N,O-donor Schiff base ligands related to intermediate forms of the TPQ cofactor in amine oxidaseshttps://puma.ub.uni-stuttgart.de/bibtex/2a8aaebdd8cf46bbb9cb3da3bf6f546b9/b_schwederskib_schwederski2019-07-15T13:41:23+02:00aminated amine benzylideneiminophenol benzylideneiminoresorcinol bond copper dihydroxyisopropylphenylacetamide dihydroxyisopropylphenylacetamide;copper interaction intermediate intermediate;topaquinone model oxidase prepn;crystal prepn;ring structure topaquinone triphenylphosphine triphenylphosphine;Schiff triphenylphosphine;hydrogen triphenylphosphine;hydroxyisopropylphenylacetamide <span data-person-type="author" class="authorEditorList "><span><span itemtype="http://schema.org/Person" itemscope="itemscope" itemprop="author"><a title="T. Sixt" itemprop="url" href="/person/1688d3389b6e8e7ef4f5ed532c4b23f12/author/0"><span itemprop="name">T. Sixt</span></a></span>, </span> and <span><span itemtype="http://schema.org/Person" itemscope="itemscope" itemprop="author"><a title="W. Kaim" itemprop="url" href="/person/1688d3389b6e8e7ef4f5ed532c4b23f12/author/1"><span itemprop="name">W. Kaim</span></a></span></span>. </span><span class="additional-entrytype-information"><span itemtype="http://schema.org/PublicationIssue" itemscope="itemscope" itemprop="isPartOf"><em><span itemprop="journal">Inorganica Chimica Acta</span>, </em> </span>(<em><span>2000<meta content="2000" itemprop="datePublished"/></span></em>)</span>Mon Jul 15 13:41:23 CEST 2019Inorganica Chimica Acta762--768Copper(I) complexes with N,O-donor Schiff base ligands related to intermediate forms of the TPQ cofactor in amine oxidases300-3022000aminated amine benzylideneiminophenol benzylideneiminoresorcinol bond copper dihydroxyisopropylphenylacetamide dihydroxyisopropylphenylacetamide;copper interaction intermediate intermediate;topaquinone model oxidase prepn;crystal prepn;ring structure topaquinone triphenylphosphine triphenylphosphine;Schiff triphenylphosphine;hydrogen triphenylphosphine;hydroxyisopropylphenylacetamide Neutral complexes (PPh3)2Cu(L) were obtained from (PPh3)2Cu(NO3) and the deprotonated forms of the three Schiff base ligands 2-(benzylideneimino)phenol (BimOH), 4-(benzylideneimino)resorcinol (Bim(OH)2) and N-(2,4-dihydroxy-5-isopropylphenyl)acetamide (DipaH3). The ligands were designed to model aminated intermediate forms of the topaquinone (TPQ) cofactor in the enzymic cycle of Cu-dependent amine oxidases. The ligands, L, are coordinated to the metal centers through imine-N and phenolate-O donor atoms to form five-membered chelate rings, in contrast to the six-membered chelate rings of salen-type Schiff base ligands. (Bim(OH)O)Cu(PPh3)2·0.5MeOH was structurally analyzed and shown to exhibit intramol. aryl-aryl interactions between the ligands and intermol. H bonds involving the free phenolic hydroxyl substituent, the coordinated phenolate O atom and the MeOH solvate mol. [on SciFinder(R)]