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Stefan Schaub Andreas Miska Dr. Jonathan Becker Dr. Stefan Zahn Prof. Dr. Doreen Mollenhauer Dr. Sadashivaiah Sakshath Prof. Dr. Volker Schünemann Prof. Dr. Siegfried Schindler 《Angewandte Chemie (International ed. in English)》2018,57(19):5355-5358
The iron(IV) oxido complex [(tmc)Fe=O(OTf)]OTf with the macrocyclic ligand 1,4,8,11‐tetramethyl‐1,4,8,11‐tetraazacyclo‐tetradecane (tmc) has been synthesized using ozone as an oxidant. By adding water to this compound the complex [(H2O)(tmc)Fe=O)](OTf)2 could be prepared. This complex is important in regard to a better understanding of the reactivity of FeIV oxido complexes. Mössbauer measurements using the solid compound showed an isomer shift of δ=0.19 mm s?1 and a quadrupole splitting ΔEQ=1.38 mm s?1, confirming the high‐valent FeIV state. DFT calculations were performed and led to an assignment of triplet spin multiplicity. Crystallographic characterization of [(H2O)(tmc)Fe=O)](OTf)2 as well as of starting materials [(tmc)Fe(CH3CN)](OTf)2 and [(tmc)Fe(OTf)]OTf together with previous results strongly suggest that [(H2O)(tmc)Fe=O)](OTf)2 was formed similar to the oxido–hydroxido tautomerism analogous to heme systems. 相似文献
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A.P. Esteves 《Tetrahedron》2007,63(14):3006-3009
The controlled-potential reduction of [1-bromo-2-methoxy-2-(prop-2′-ynyloxy)ethyl]benzene (1a), 1-[2-bromo-2-phenyl-1-(prop-2′-ynyloxy)ethyl]-4-methoxybenzene (1b) and 2-bromo-3-(3′,4′-dimethoxyphenyl)-3-propargyloxypropanamide (1c) catalysed by (1,4,8,11-tetramethyl-1,4,8,11-tetraazacyclotetradecane)nickel(I), [Ni(tmc)]+, at a vitreous carbon cathode in DMF/Et4NBF4 leads to 2-methoxy-4-methylene-3-phenyl-tetrahydrofuran (2a), 2-(4′-methoxyphenyl)-4-methylene-3-phenyl-tetrahydrofuran (2b) and 2-(3′,4′-dimethoxyphenyl)-3-carbamoyl-4-methylenetetrahydrofuran (2c), respectively, in very high yields. 相似文献
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Gerald R. Willey Miles T. Lakin Nathaniel W. Alcock Christopher J. Samuel 《Journal of inclusion phenomena and macrocyclic chemistry》1994,15(3):293-304
The X-ray crystal structure of 1,4,8,11-tetramethyl-1,4,8,11-tetraazacyclotetradecane has been determined. The neutral ligand crystallises in the triclinic space groupP
with unit cell parametersa=8.467(4),b=10.057(5),c=10.637(5) Å, =67.68(3), =75.38(4), =76.34(4)°,V=800.75 Å3 andD
c=1.063 g cm–3 forZ=2.R=0.047 for 2140 unique observed (I/(I)2.0) reflections (R
w=0.052). Two crystallographically independent molecules are observed. Both are centrosymmetric and adopt a mesodentate conformation. Molecule (1) is identified as the (R, S, S, R)-[trans-IV] isomer and molecule (2) as the (R, R, S, S)-[trans-III] isomer. Molecular mechanics calculations provide a basis for understanding the structural and energetic relationships between the neutral and protonated forms of this tetraazamacrocyclic ligand.
Supplementary Data relating to this article have been deposited with the British Library at Boston Spa, Wetherby, West Yorkshire, U.K. as Supplementary Publication No. 82149 (13 pages). 相似文献
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