Article
Chemistry, Inorganic & Nuclear
Tian Xing, Timothy J. Prior, Kai Chen, Carl Redshaw
Summary: A variety of complexes based on calixarene structures were synthesized and evaluated for their potential as catalysts in the ring opening polymerization of epsilon-caprolactone, delta-valerolactone, and rac-lactide. The complexes bearing oxacalixarene structures exhibited better activities compared to azacalixarene-based pre-catalysts.
DALTON TRANSACTIONS
(2021)
Review
Polymer Science
Jianqun Wang, Youhua Tao
Summary: The review highlights the use of various catalysts, especially metal-based catalysts, for controlled ROP of OCAs. It also summarizes recent progress on the organocatalytic ROP of OCAs and discusses the future development of this method for sustainable polyester synthesis.
MACROMOLECULAR RAPID COMMUNICATIONS
(2021)
Review
Polymer Science
Jiaxi Xu, Nikos Hadjichristidis
Summary: The incorporation of heteroatom-containing weak bonds along polymer backbones has become a popular tool to accelerate degradation. Many methods have been reported for the synthesis of degradable heteroatom-containing polymers based on step-growth polymerization and chain-growth ring-opening polymerization. Ring-opening metathesis polymerization has emerged as an approach for the synthesis of various types of degradable polymers. This review covers the synthesis of different heteroatom-containing degradable polymers via ring-opening metathesis polymerization and their degradation mechanisms under different conditions.
PROGRESS IN POLYMER SCIENCE
(2023)
Article
Polymer Science
Jian Lin, Peng Wang, Lei Fan, Tian Xiao, Jianhua Cheng, Xia Chen
Summary: Bi- and tetra-lithium quinolyl/pyridyl-amino complexes were synthesized and characterized, showing high catalytic activity in the polymerization of rac-lactice and e-caprolactone. The number of metal centers and ligand structures were found to be crucial factors in determining the reactivity of the catalyst in ring-opening polymerization (ROP).
Article
Chemistry, Inorganic & Nuclear
Xiaowei Xu, Han Lu, Gen Luo, Xiaohui Kang, Yi Luo
Summary: The origin of opposite reactivity in the ring-opening polymerizations of lactide (LA) and cyclohexene oxide (CHO) catalyzed by redox-switchable bis(imino)pyridine iron complexes has been computationally elucidated. Larger geometrical deformation leads to lower activity of the oxidized form (Fe-ox) of the iron catalyst toward LA polymerization compared to the reduced analogue (Fe-red), while the higher activity of Fe-ox toward CHO polymerization is attributed to stronger interaction with CHO moieties due to its higher electrophilicity. This theoretical understanding has led to the computational modeling of various Fe-ox analogues with modified substituents to increase their electrophilicity and lower energy barriers in CHO enchainment.
INORGANIC CHEMISTRY FRONTIERS
(2021)
Article
Polymer Science
Joanna Jaworska, Michal Sobota, Malgorzata Pastusiak, Michal Kawalec, Henryk Janeczek, Piotr Rychter, Kamila Lewicka, Piotr Dobrzynski
Summary: This work presents the results of research on the preparation of bioresorbable functional polyestercarbonates containing side carboxyl groups. The simplified one-step method allows obtaining copolymers with all carbonate units containing carboxyl groups, avoiding the issue of heavy metals residue from the traditional method.
Article
Multidisciplinary Sciences
Luca Muenzfeld, Sebastian Gillhuber, Adrian Hauser, Sergei Lebedkin, Pauline Haedinger, Nicolai D. Knoefel, Christina Zovko, Michael T. Gamer, Florian Weigend, Manfred M. Kappes, Peter W. Roesky
Summary: Cyclic nanometre-scale sandwich complexes with metal ion coordination by two planar aromatic organic rings were synthesized. These complexes have broad applications in catalysis, synthesis, electrochemistry, nanotechnology, materials science, and medicine. This study presents the design, synthesis, and characterization of a series of circular sandwich compounds, called "cyclocenes". These cyclocenes consist of 18 repeating units, forming almost perfectly circular rings, and their formation is facilitated by the interplay of ionic metal-to-ligand bonds, the bulkiness of the ligand system, and energy gain on ring closure.
Article
Polymer Science
Sreenath Pappuru, Venkatachalam Ramkumar, Debashis Chakraborty
Summary: Monomeric titanium and zirconium complexes were successfully synthesized and studied for their catalytic activity in the ring-opening polymerization of epsilon-caprolactone and rac-lactide. The single-site zirconium alkoxide complex showed the best catalytic activity, efficiently converting monomers into polymers in high yield under solvent-free conditions within a short period of time.
POLYMERS FOR ADVANCED TECHNOLOGIES
(2021)
Article
Chemistry, Multidisciplinary
J. Drake Johnson, Samuel W. Kaplan, Jozsef Toth, Zian Wang, Mitchell Maw, Sergei S. Sheiko, Aleksandr V. Zhukhovitskiy
Summary: ROMP of carbodiimides initiated and catalyzed by an iridium guanidinate complex produced a series of heteroatom-rich polymers. A strategy of carbodiimide ring-opening metathesis polymerization and derivatization was developed to synthesize nitrogen-rich macromolecules. This work advances the foundations of metathesis chemistry and allows for systematic investigations of structure-folding-property relationships in nitrogen-rich polymers.
ACS CENTRAL SCIENCE
(2023)
Article
Biochemistry & Molecular Biology
Maxim V. V. Zabalov, Badma N. N. Mankaev, Mikhail P. P. Egorov, Sergey S. S. Karlov
Summary: Density functional theory simulations were conducted to investigate the ring-opening copolymerization of epsilon-caprolactone and L-lactide using a novel gallium complex with an aminobis(phenolate) ligand. The results show that the copolymerization with this catalyst exhibits a faster polymerization rate for epsilon-caprolactone than for L-lactide, suggesting the formation of a predominantly block copolymer composed of epsilon-caprolactone and L-lactide.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2022)
Article
Chemistry, Multidisciplinary
Jiandong Li, Fusheng Liu, Yalei Liu, Yong Shen, Zhibo Li
Summary: This study presents a method for chemoselective controlled ring-opening polymerization of bio-renewable bifunctional alpha-methylene-delta-valerolactone (MVL) using strong base/urea binary catalysts. The obtained high molecular weight polyester exhibits good mechanical properties. The pristine monomer can be recovered through thermolysis, establishing a closed-loop life cycle.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Multidisciplinary
Xiao Jiang, Na Zhao, Zhibo Li
Summary: A bifunctional H-bonding catalyst SQ-1 and the binary H-bonding catalytic system consisting of squaramides (SQ-2 to SQ-6) and DBU were discovered to efficiently promote the stereoselective ring-opening polymerization (ROP) of rac-lactide at room temperature. The resulting polylactides exhibited controlled molecular weights and high tacticity.
CHINESE JOURNAL OF CHEMISTRY
(2021)
Article
Chemistry, Multidisciplinary
Hui Li, Jerome Ollivier, Sophie M. Guillaume, Jean-Francois Carpentier
Summary: This study reports the first chemical synthesis of poly(3-thiobutyrolactone) (P3TB) through ring-opening polymerization. The reactions proceed rapidly in the presence of various metal-based catalysts, and high selectivity can be achieved by manipulating reaction conditions and catalyst systems. The topology and stereochemistry of the resulting polymer have been characterized.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Polymer Science
James McQuade, Mya I. Serrano, Frieder Jakle
Summary: The incorporation of main group elements into polymers enables the synthesis of functional materials with unique molecular structures and chemical properties. Ring-opening metathesis polymerization (ROMP) is a versatile method for generating new main group element-functionalized materials.
Article
Chemistry, Multidisciplinary
Tengda Zhao, Kongying Zhu, Xiaoliang Yu, Xiaoyan Yuan, Lixia Ren
Summary: This study demonstrates that introducing a sufficient length of polystyrene spacer chain can protect the ruthenium atom in the third generation Grubbs catalyst (G3) and effectively control the ROMP process of macromonomers with tertiary amine groups.
CHINESE JOURNAL OF CHEMISTRY
(2021)
Article
Chemistry, Applied
Daniel Becker, Dirk Bockfeld, Matthias Tamm
Summary: In this study, two complexes were obtained by reacting the bidentate [P,N] ligand with [Ir(COD)Cl] and adding different ligands, and further reaction yielded a diiridium tetrahydride. Crystal structure analysis of the three complexes revealed that the position of the hydrogen atoms in one of the complexes could be refined freely. Since the first complex is a validated catalyst, the performance of the two complexes in deuterium labeling reactions was compared.
ADVANCED SYNTHESIS & CATALYSIS
(2023)
Article
Chemistry, Multidisciplinary
You-Jie Yu, Michael Schaefer, Constantin G. Daniliuc, Ryan Gilmour
Summary: A catalysis-based regioselective method for the synthesis of compact, highly functionalized products from trifluoromethyl substituted 1,3-dienes has been developed. The new method allows E,Z-mixed dienes to be converted to a single E-alkene isomer and utilizes an inexpensive and convenient I(I)/I(III) catalysis platform. This method enables the synthesis of delta-fluoro-alcohol and amine derivatives in a single operation, and is compatible with various nucleophiles.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Xiaoming Jie, Chaohuang Chen, Constantin G. Daniliuc, Gerald Kehr, Gerhard Erker
Summary: The hydroboration of styrene or vinylcyclohexane with the IMes(C6F5)BH+ cation followed by deprotonation provides a convenient synthetic route to boraalkenes [B]=CHCH2R. The in-situ generated IMes(SCN)BH+ system reacts similarly with 1,1-diphenylethene, resulting in the formation of isothiocyanato-substituted boraalkene. The boraalkenes participate in [2+2] cycloaddition reactions with heterocumulenes, yielding respective four-membered heterocycles. The addition of borane HB(C6F5)(2) to [B]=CHCH2R+CO2 cycloadducts leads to cleavage of the central B-C sigma-bond.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Inorganic & Nuclear
Lukas Koerner, Linpan Yang, Dirk Bockfeld, Matthias Tamm
Summary: In this study, a series of 1,1-enediamines were synthesized and transformed into corresponding complexes with gold, palladium, and boron ligands. The new complexes were fully characterized by NMR spectroscopy and X-ray diffraction analysis, revealing their similarities to N-heterocyclic olefins in terms of structural features.
JOURNAL OF ORGANOMETALLIC CHEMISTRY
(2023)
Article
Chemistry, Medicinal
Tobias Schierling, Beatrice Tosi, Clara Eisenhardt, Sophie Reining, Constantin G. Daniliuc, Christoph Brenker, Timo Struenker, Bernhard Wuensch
Summary: This article introduces a new and more effective inhibitor for studying sperm swimming behavior. The inhibitor is structurally simpler and easier to synthesize compared to existing inhibitors, and shows even better potency. It is envisioned to be widely used in future studies on the physiology of CatSper in sperm.
ACS PHARMACOLOGY & TRANSLATIONAL SCIENCE
(2023)
Article
Chemistry, Multidisciplinary
Yujie Liang, Fritz Paulus, Constantin G. Daniliuc, Frank Glorius
Summary: We report a BF3-catalyzed [2 + 2] cycloaddition reaction between aldehydes and bicyclo[1.1.0]butanes (BCBs) to access polysubstituted 2-oxabicyclo[2.1.1]hexanes. A new BCB containing an acyl pyrazole group was discovered, which not only facilitates the reactions but also allows for diverse downstream transformations. Additionally, aryl and vinyl epoxides can be used as substrates that undergo cycloaddition with BCBs after in situ rearrangement to aldehydes. These results will promote the exploration of complex sp(3)-rich bicyclic frameworks and BCB-based cycloaddition chemistry.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Inorganic & Nuclear
Lilian Sophie Szych, Karsten Paul Ludtke, Alexander Villinger, Dirk Bockfeld, Matthias Tamm, Axel Schulz
Summary: The synthesis of sterically demanding 2,6-bis-(2,4,6-trimethylphenyl)-phenyl (Ter)-stabilized and H-substituted diphosphanes via conversion of phosphide with secondary chlorophosphanes is described. The resulting potassium phosphinophosphides can be further functionalized and selectively used to synthesize Si-substituted diphosphanes or triphosphanes.
INORGANIC CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Roman Kleinmans, Subhabrata Dutta, Kristers Ozols, Huiling Shao, Felix Schafer, Rebecca E. Thielemann, Hok Tsun Chan, Constantin G. Daniliuc, Kendall N. Houk, Frank Glorius
Summary: The ortho-selective intermolecular photocycloaddition of bicyclic aza-arenes is reported, utilizing a strain-release approach. This reaction enables the construction of C-(sp(3))-rich bicyclo-[2.1.1]-hexanes directly connected to N-heteroarenes. Photophysical experiments and DFT calculations reveal the mechanism of this selective intermolecular photocycloaddition.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Biochemistry & Molecular Biology
Gina Vasile Scaeteanu, Constantin G. Daniliuc, Rodica Olar, Mihaela Badea
Summary: A complex [Zn(bpy)(acr)(2)]center dot H2O was converted into a coordination polymer [Zn(bpy)(acr)(HCOO)](n) in a DMF medium. The polymer was fully characterized through crystallographic analysis, IR, and thermogravimetric analysis. The obtained complex, with its unique composition and structure, is of current interest and rarely reported in the literature.
Article
Chemistry, Inorganic & Nuclear
Adinarayana Doddi, Thomas Bannenberg, Dirk Bockfeld, Matthias Tamm
Summary: Half-sandwich iridium complexes of [(eta(5)-C5Me5){(NHC)E}IrCl] (E=P, As) were synthesized using N-heterocyclic carbene (NHC) adducts of (IDipp)ESiMe3 and (IMes)ESiMe3 with [(eta(5)-C5Me5)IrCl2](2). The X-ray diffraction analysis of [(eta(5)-C5Me5){(IDipp)As}IrCl] confirmed its molecular structure, revealing the first structurally authenticated NHC-arsinidenide complex with a shorter Ir-As bond length and significant metal-arsenic pi-interaction, as supported by theoretical calculations.
ZEITSCHRIFT FUR ANORGANISCHE UND ALLGEMEINE CHEMIE
(2023)
Article
Chemistry, Multidisciplinary
Benedikt Sieland, Marcel Stahn, Roland Schoch, Constantin Daniliuc, Sebastian Spicher, Stefan Grimme, Andreas Hansen, Jan Paradies
Summary: An isostructural series of boron/phosphorus Lewis pairs were investigated systematically. The association constants of the Lewis pairs were determined and thermodynamic parameters were extracted at different temperatures. The stabilization of the Lewis adduct increased with the size of the dispersion energy donor groups, despite the donor and acceptor properties of the Lewis pairs remaining largely unchanged. This data was used to challenge state-of-the-art quantum chemical methods and resulted in an enhanced workflow for accurately determining the thermochemical properties of weakly bound Lewis pairs.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Fabian Hoeglsperger, Fayaz Ali Larik, Changzhuang Bai, Maximilian D. Seyfried, Constantin Daniliuc, Henning Klaasen, Pall Thordarson, Jonathon E. Beves, Bart Jan Ravoo
Summary: In this study, water-soluble arylazoisoxazole photoswitches were introduced. The photostationary states and reversible photoisomerization between E- and Z-isomers were observed, indicating their potential for photoresponsive host-guest chemistry in water. Furthermore, hydrogel properties can be manipulated reversibly with light. Overall, arylazoisoxazoles have great potential as molecular photoswitches in aqueous media.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Chemistry, Multidisciplinary
Zi-Xuan Wang, Keith Livingstone, Carla Huempel, Constantin G. Daniliuc, Christian Mueck-Lichtenfeld, Ryan Gilmour
Summary: Fluorinated small molecules are commonly used in the field of functional small molecules. Researchers have developed creative approaches to access these important materials by utilizing iodine(I)/iodine(III) catalysis to convert abundant alkene substrates into high-value (di)fluorinated products. They also discovered that enynes can be used as proxies for styrenes, simplifying the process and enabling the generation of highly versatile homopropargylic difluorides.
Article
Chemistry, Multidisciplinary
Timo Stuenkel, Kathrin Siebold, Daichi Okumatsu, Kazuki Murata, Louise Ruyet, Constantin G. Daniliuc, Ryan Gilmour
Summary: The regio- and enantio-selective dearomatization of phenols has been achieved using I(i)/I(iii) catalysis enabled fluorination. The reaction is highly selective and efficient, offering great potential in the field of hydroxylation chemistry.
Article
Chemistry, Organic
Tobias Winge, Dirk Schepmann, Judith Schmidt, Constantin Daniliuc, Ernst-Ulrich Wuerthwein, Bernhard Wuensch
Summary: Spirocyclic scaffolds are important in drug discovery as they enhance specific interactions with protein binding sites. This study synthesized a series of spirocyclic compounds and found that one of them exhibited favorable pharmacological and physicochemical properties.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2023)
