Koszinowski, Konrad

[["dc.bibliographiccitation.artnumber","anie.202210211"],["dc.bibliographiccitation.issue","43"],["dc.bibliographiccitation.journal","Angewandte Chemie International Edition"],["dc.bibliographiccitation.volume","61"],["dc.contributor.affiliation","Kreyenschmidt, Friedrich; 1\r\nInstitut für Organische und Biomolekulare Chemie\r\nUniversität Göttingen\r\nTammannstraße 2 37077 Göttingen Germany"],["dc.contributor.affiliation","Eisele, Niklas F.; 1\r\nInstitut für Organische und Biomolekulare Chemie\r\nUniversität Göttingen\r\nTammannstraße 2 37077 Göttingen Germany"],["dc.contributor.affiliation","Hevelke, Valentin; 1\r\nInstitut für Organische und Biomolekulare Chemie\r\nUniversität Göttingen\r\nTammannstraße 2 37077 Göttingen Germany"],["dc.contributor.affiliation","Rahrt, Rene; 1\r\nInstitut für Organische und Biomolekulare Chemie\r\nUniversität Göttingen\r\nTammannstraße 2 37077 Göttingen Germany"],["dc.contributor.affiliation","Kreyenschmidt, Anne‐Kathrin; 2\r\nInstitut für Anorganische Chemie\r\nUniversität Göttingen\r\nTammannstraße 4 37077 Göttingen Germany"],["dc.contributor.affiliation","Koszinowski, Konrad; 1\r\nInstitut für Organische und Biomolekulare Chemie\r\nUniversität Göttingen\r\nTammannstraße 2 37077 Göttingen Germany"],["dc.contributor.author","Kreyenschmidt, Friedrich"],["dc.contributor.author","Eisele, Niklas F."],["dc.contributor.author","Hevelke, Valentin"],["dc.contributor.author","Rahrt, Rene"],["dc.contributor.author","Kreyenschmidt, Anne‐Kathrin"],["dc.contributor.author","Koszinowski, Konrad"],["dc.date.accessioned","2022-11-28T09:40:41Z"],["dc.date.available","2022-11-28T09:40:41Z"],["dc.date.issued","2022-09-26"],["dc.date.updated","2022-11-27T10:11:07Z"],["dc.description.abstract","Abstract\r\nAnionic coordination polymerizations proceed via highly reactive intermediates, whose in situ analysis has remained difficult. Here, we show that electrospray‐ionization mass spectrometry is a promising method to obtain detailed information on the polymerization process. Focusing on polymerization reactions of 1,3‐dienes initiated by CoCl2/RLi (R=Me, nBu, tBu, Ph), we directly observe the growing polymer chains and characterize the active anionic cobalt centers by gas‐phase fragmentation experiments. On the basis of these results, we suggest a plausible mechanism for the polymerization reaction. Moreover, the ESI mass spectra permit the determination of molecular weight distributions, which are in good agreement with those derived from NMR‐spectroscopic as well as MALDI mass‐spectrometric measurements, and afford a wealth of kinetic data."],["dc.description.abstract","Negative‐ion mode ESI mass spectrometry permits the direct observation of anionic polymers resulting from the reaction of 1,3‐dienes with CoCl2 and organolithium reagents.\r\n\r\nimage"],["dc.description.sponsorship","Deutsche Forschungsgemeinschaft http://dx.doi.org/10.13039/501100001659"],["dc.identifier.doi","10.1002/anie.202210211"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/117297"],["dc.language.iso","en"],["dc.notes.intern","DOI-Import GROB-597"],["dc.relation.eissn","1521-3773"],["dc.relation.issn","1433-7851"],["dc.rights","This is an open access article under the terms of the Creative Commons Attribution‐NonCommercial License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited and is not used for commercial purposes."],["dc.rights.uri","http://onlinelibrary.wiley.com/termsAndConditions#vor"],["dc.title","In‐Situ Analysis of Anionic Coordination Polymerizations by Electrospray‐Ionization Mass Spectrometry"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","152"],["dc.bibliographiccitation.issue","4"],["dc.bibliographiccitation.journal","ChemistryOpen"],["dc.bibliographiccitation.lastpage","160"],["dc.bibliographiccitation.volume","3"],["dc.contributor.author","Kotyrba, Ursula M."],["dc.contributor.author","Proepper, Kevin"],["dc.contributor.author","Sachs, Eike-F."],["dc.contributor.author","Myanovska, Anastasiya"],["dc.contributor.author","Joppe, Tobias"],["dc.contributor.author","Lissy, Friederike"],["dc.contributor.author","Sheldrick, George M."],["dc.contributor.author","Koszinowski, Konrad"],["dc.contributor.author","Diederichsen, Ulf"],["dc.date.accessioned","2018-11-07T09:37:00Z"],["dc.date.available","2018-11-07T09:37:00Z"],["dc.date.issued","2014"],["dc.description.abstract","The DNA bisintercalator triostin A is structurally based on a disulfide-bridged depsipeptide scaffold that provides preorganization of two quinoxaline units in 10.5 angstrom distance. Triostin A analogues are synthesized with nucleobase recognition units replacing the quinoxalines and containing two additional recognition units in between. Thus, four nucleobase recognition units are organized on a rigid template, well suited for DNA double strand interactions. The new tetra-nucleobase binders are synthesized as aza-TANDEM derivatives lacking the N-methylation of triostin A and based on a cyclopeptide backbone. Synthesis of two tetra-nucleobase aza-TANDEM derivatives is established, DNA interaction analyzed by microscale thermophoresis, cytotoxic activity studied and a nucleobase sequence dependent self-aggregation investigated by mass spectrometry."],["dc.description.sponsorship","Deutsche Forschungsgemeinschaft [DI 542/7-1, SH 14/5-1]"],["dc.identifier.doi","10.1002/open.201400001"],["dc.identifier.isi","000341175700005"],["dc.identifier.pmid","25478311"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/11914"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/32739"],["dc.notes.intern","Merged from goescholar"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Wiley-v C H Verlag Gmbh"],["dc.relation.issn","2191-1363"],["dc.rights","CC BY-NC 3.0"],["dc.rights.uri","https://creativecommons.org/licenses/by-nc/3.0"],["dc.title","Triostin A Derived Cyclopeptide as Architectural Template for the Alignment of Four Recognition Units"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","13376"],["dc.bibliographiccitation.issue","58"],["dc.bibliographiccitation.journal","Chemistry – A European Journal"],["dc.bibliographiccitation.lastpage","13384"],["dc.bibliographiccitation.volume","25"],["dc.contributor.author","Kolter, Marlene"],["dc.contributor.author","Koszinowski, Konrad"],["dc.date.accessioned","2020-12-10T14:05:54Z"],["dc.date.available","2020-12-10T14:05:54Z"],["dc.date.issued","2019"],["dc.description.abstract","Abstract Despite their considerable practical value, palladium/1,3‐diene‐catalyzed cross‐coupling reactions between Grignard reagents RMgCl and alkyl halides AlkylX remain mechanistically poorly understood. Herein, we probe the intermediates formed in these reactions by a combination of electrospray‐ionization mass spectrometry, UV/Vis spectroscopy, and NMR spectroscopy. According to our results and in line with previous hypotheses, the first step of the catalytic cycle brings about transmetalation to afford organopalladate anions. These organopalladate anions apparently undergo SN2‐type reactions with the AlkylX coupling partner. The resulting neutral complexes then release the cross‐coupling products by reductive elimination. In gas‐phase fragmentation experiments, the occurrence of reductive eliminations was observed for anionic analogues of the neutral complexes. Although the actual catalytic cycle is supposed to involve chiefly mononuclear palladium species, anionic palladium nanoclusters [PdnR(DE)n]−, (n=2, 4, 6; DE=diene) were also observed. At short reaction times, the dinuclear complexes usually predominated, whereas at longer times the tetra‐ and hexanuclear clusters became relatively more abundant. In parallel, the formation of palladium black pointed to continued aggregation processes. Thus, the present study directly shows dynamic behavior of the palladium/diene catalyst system and degradation of the active catalyst with increasing reaction time."],["dc.description.abstract","Transient nanoclusters: A combination of ESI mass spectrometry, gas‐phase fragmentation experiments, and UV/Vis and NMR spectroscopy revealed the presence of anionic nanoclusters [PdnR(DE)n]− (n=2, 4, 6; DE=diene) in palladium/1,3‐diene‐catalyzed cross‐coupling reactions. At short reaction times, the dinuclear complexes usually predominated, whereas at longer times, the tetra‐ and hexanuclear clusters became more abundant, and the formation of palladium black indicated ongoing aggregation processes (see figure; DEI=isoprene). image"],["dc.description.sponsorship","Niedersächsische Ministerium für Wissenschaft und Kultur http://dx.doi.org/10.13039/501100010570"],["dc.identifier.doi","10.1002/chem.201902610"],["dc.identifier.eissn","1521-3765"],["dc.identifier.issn","0947-6539"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/69701"],["dc.language.iso","en"],["dc.notes.intern","DOI Import GROB-354"],["dc.rights","This is an open access article under the terms of the Creative Commons Attribution‐NonCommercial License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited and is not used for commercial purposes."],["dc.title","Formation of Transient Anionic Metal Clusters in Palladium/Diene‐Catalyzed Cross‐Coupling Reactions"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.issue","43"],["dc.bibliographiccitation.journal","Angewandte Chemie"],["dc.bibliographiccitation.volume","134"],["dc.contributor.affiliation","Kreyenschmidt, Friedrich; 1\nInstitut für Organische und Biomolekulare Chemie\nUniversität Göttingen\nTammannstraße 2 37077 Göttingen Deutschland"],["dc.contributor.affiliation","Eisele, Niklas F.; 1\nInstitut für Organische und Biomolekulare Chemie\nUniversität Göttingen\nTammannstraße 2 37077 Göttingen Deutschland"],["dc.contributor.affiliation","Hevelke, Valentin; 1\nInstitut für Organische und Biomolekulare Chemie\nUniversität Göttingen\nTammannstraße 2 37077 Göttingen Deutschland"],["dc.contributor.affiliation","Rahrt, Rene; 1\nInstitut für Organische und Biomolekulare Chemie\nUniversität Göttingen\nTammannstraße 2 37077 Göttingen Deutschland"],["dc.contributor.affiliation","Kreyenschmidt, Anne‐Kathrin; 2\nInstitut für Anorganische Chemie\nUniversität Göttingen\nTammannstraße 4 37077 Göttingen Deutschland"],["dc.contributor.affiliation","Koszinowski, Konrad; 1\nInstitut für Organische und Biomolekulare Chemie\nUniversität Göttingen\nTammannstraße 2 37077 Göttingen Deutschland"],["dc.contributor.author","Kreyenschmidt, Friedrich"],["dc.contributor.author","Eisele, Niklas F."],["dc.contributor.author","Hevelke, Valentin"],["dc.contributor.author","Rahrt, Rene"],["dc.contributor.author","Kreyenschmidt, Anne‐Kathrin"],["dc.contributor.author","Koszinowski, Konrad"],["dc.date.accessioned","2022-11-28T09:42:35Z"],["dc.date.available","2022-11-28T09:42:35Z"],["dc.date.issued","2022-09-26"],["dc.date.updated","2022-11-27T10:11:16Z"],["dc.description.sponsorship","Deutsche Forschungsgemeinschaft http://dx.doi.org/10.13039/501100001659"],["dc.identifier.doi","10.1002/ange.202210211"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/117306"],["dc.language.iso","en"],["dc.publisher",""],["dc.rights","This is an open access article under the terms of the Creative Commons Attribution‐NonCommercial License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited and is not used for commercial purposes."],["dc.rights",""],["dc.title","In‐Situ‐Analyse Anionischer Koordinationspolymerisationen durch Elektrosprayionisations‐Massenspektrometrie"],["dc.type","journal_article"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","5590"],["dc.bibliographiccitation.issue","13"],["dc.bibliographiccitation.journal","Dalton Transactions"],["dc.bibliographiccitation.lastpage","5597"],["dc.bibliographiccitation.volume","45"],["dc.contributor.author","Brouillet, Etienne V."],["dc.contributor.author","Kennedy, Alan R."],["dc.contributor.author","Koszinowski, Konrad"],["dc.contributor.author","McLellan, Ross"],["dc.contributor.author","Mulvey, Robert E."],["dc.contributor.author","Robertson, Stuart D."],["dc.date.accessioned","2017-01-20T14:29:11Z"],["dc.date.accessioned","2021-10-27T13:12:32Z"],["dc.date.available","2017-01-20T14:29:11Z"],["dc.date.available","2021-10-27T13:12:32Z"],["dc.date.issued","2016"],["dc.description.abstract","The cationic magnesium moiety of magnesium organohaloaluminate complexes, relevant to rechargeable Mg battery electrolytes, typically takes the thermodynamically favourable dinuclear [Mg2Cl3]+ form in the solid-state. We now report that judicious choice of Lewis donor allows the deliberate synthesis and isolation of the hitherto only postulated mononuclear [MgCl]+ and trinuclear [Mg3Cl5]+ modifications, forming a comparable series with a common aluminate anion [(Dipp)(Me3Si)NAlCl3]−. By pre-forming the Al–N bond prior to introduction of the Mg source, a consistently reproducible protocol is reported. Usage of the green solvent 2-methyltetrahydrofuran in place of THF in the context of Mg/Al battery electrolyte type complexes is also promoted."],["dc.identifier.doi","10.1039/C6DT00531D"],["dc.identifier.isi","000372608300022"],["dc.identifier.pmid","26916737"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/14173"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/91699"],["dc.language.iso","en"],["dc.notes.intern","Migrated from goescholar"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Royal Soc Chemistry"],["dc.relation.issn","1477-9234"],["dc.relation.issn","1477-9226"],["dc.relation.orgunit","Fakultät für Chemie"],["dc.rights","Goescholar"],["dc.rights.access","openAccess"],["dc.rights.uri","https://goescholar.uni-goettingen.de/licenses"],["dc.subject","cationic magnesium; aluminate complexes"],["dc.title","Exposing elusive cationic magnesium–chloro aggregates in aluminate complexes through donor control"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]