Achiral [Ru2(μ-O2CR)4(MeOH)2](PF6) (R = CH3 or C6H5) reacts with the chiral diphosphines R,R- and S,S-Chiraphos (two chiral centers on ligand between the coordinating P atoms) and R-Prophos (one chiral center on ligand between the coordinating P atoms) leading to a disassembly of the paddlewheel core and the highly diastereoselective production of Λ-[Ru(η(2)-O2CC6H5)(η(2)-R,R-Chiraphos)2](PF6) (Λ-R,R-III), Δ-[Ru(η(2)-O2CC6H5)(η(2)-S,S-Chiraphos)2](PF6) (Δ-S,S-III) (the R = CH3 complexes of Chiraphos were reported in a earlier communication in this journal), and Λ-[Ru(η(2)-O2CCH3)(η(2)-R-Prophos)2](PF6) (Λ-R,R-VI), respectively, in high yield and purity. Reactions of the same starting material with R,R- and S,S-o-tolyl-Dipamp (chiral centers are the coordinating P-atoms) lead to an inversion in the chirality-at-metal producing Λ-[Ru(η(2)-O2CC6H5)(η(2)-S,S-o-tolyl-Dipamp)2](PF6) (Λ-S,S-IV), Δ-[Ru(η(2)-O2CC6H5)(η(2)-R,R-o-tolyl-Dipamp)2](PF6) (Δ-R,R-IV), Λ-[Ru(η(2)-O2CCH3)(η(2)-S,S-o-tolyl-Dipamp)2](PF6) (Λ-S,S-V), and Δ-[Ru(η(2)-O2CCH3)(η(2)-R,R-o-tolyl-Dipamp)2](PF6) (Δ-R,R-V). X-ray crystallography of all but Λ-S,S-V and Δ-R,R-V and solid-state circular dichroism (CD) show that only the indicated diastereomers are present in the solid-state. Solution CD measurements and (31)P NMR also indicate their predominance in solution.
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http://dx.doi.org/10.1021/ic401908t | DOI Listing |
J Am Chem Soc
January 2025
State Key Laboratory of Fine Chemicals, Frontiers Science Center for Smart Materials, Dalian University of Technology, 2 Linggong Road, Dalian 116024, China.
Herein, we propose to synthesize stereoblock polythioethers through the chain shuttling enantioselective ring-opening polymerization (ROP) of thiiranes. The use of diastereoisomeric dinuclear Cr complexes with optimized steric hindrance allowed the production of polythioethers with both a head-to-tail content and isotacticity of >99%. In particular, the introduction of dithiols enabled the synthesis of stereoblock polythioethers via a chain shuttling process, thus producing sulfhydryl-telechelic polythioethers with tunable thermal properties.
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January 2025
Department of Applied Physics, School of Engineering Sciences, KTH Royal Institute of Technology, AlbaNova University Center, SE-10691, Stockholm, Sweden.
Non-trivial band topology along with magnetism leads to different novel quantum phases. When time-reversal symmetry is broken in three-dimensional topological insulators (TIs) through, e.g.
View Article and Find Full Text PDFNat Commun
January 2025
State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Frontiers Science Center for New Organic Matter, Haihe Laboratory of Sustainable Chemical Transformations, Nankai University 94 Weijin Road, Tianjin, China.
The diverse utility of acyclic vinylsilanes has driven the interest in the synthesis of enantioenriched vinylsilanes bearing a Si-stereogenic center. However, the predominant approaches for catalytic asymmetric generation of Si-stereogenic vinylsilanes have mainly relied on transition metal-catalyzed reactions of alkynes with different silicon sources. Here we successfully realize the enantioselective synthesis of linear silicon-stereogenic vinylsilanes with good yields and enantiomeric ratios from simple alkenes under rhodium catalysis.
View Article and Find Full Text PDFJ Am Chem Soc
January 2025
Engineering Research Center of Photoenergy Utilization for Pollution Control and Carbon Reduction, Ministry of Education, College of Chemistry, Central China Normal University, 152 Luoyu Road, Wuhan 430079, P. R. China.
-cycloalkenes are abundant in bioactive natural products and have been used as powerful tools in chemical biology and drug discovery. However, strategies for the modular synthesis of -cycloalkenes, especially planar-chiral medium-sized ones, with high efficiency and selectivity, still remain elusive. Herein, we report a Pd-catalyzed asymmetric [7 + 2] cyclization strategy to address this challenge.
View Article and Find Full Text PDFNano Lett
January 2025
Zhejiang Engineering Research Center for Tissue Repair Materials and Wenzhou Key Laboratory of Biomaterials and Engineering and Wenzhou Key Laboratory of Biophysics, Wenzhou Institute, University of Chinese Academy of Sciences, Wenzhou 325001, China.
Saccharides and peptides with markedly disparate stereochemical features serve as pivotal chiral molecular partners in living systems. The importance of glycosylation in influencing glycopeptide self-assembly has been recognized. However, how different chiral combinations of saccharides and peptides influence the macroscopic hydrogel mechanics, fiber nanomechanics, asymmetric molecular packing, and thermodynamic changes during glycopeptide self-assembly remains unknown.
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