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191.
Cameron Jones David P. Mills Richard P. Rose Andreas Stasch William D. Woodul 《Journal of organometallic chemistry》2010,695(22):2410-2417
Reactions of the anionic gallium(I) heterocycle salt, [K(tmeda)][Ga(DAB)] (DAB = {N(Dip)C(H)}2; Dip = C6H3Pri2-2,6), with a series of groups 6-9 and 11 metal halide complexes have given rise to the metal gallyl complexes, [CpCr(IMes){Ga(DAB)}] (IMes = :C{(Mes)NC(H)}2; Mes = mesityl), [M(tmeda){Ga(DAB)}2] (M = Mn, Fe or Co) and [Cu(dppe){Ga(DAB)}] (dppe = 1,2-bis(diphenylphosphino)ethane). The majority of the complexes have been crystallographically characterized. The reactivity of the previously reported copper(I) gallyl complex, [(IPr)Cu{Ga(DAB)}] (IPr = :C{(Dip)NC(H)}2), towards a variety of unsaturated substrates has been explored. Three crystallographically characterized complexes have arisen from this phase of the study, viz. [(IPr)CuCCPh], [(IPr)Cu{Ga(DAB)}(CNBut)] and [(IPr)Cu{κ1-OC(O)C(CNHDip)(NHDip)}]. The results of these investigations show that the reactivity of [(IPr)Cu{Ga(DAB)}] is significantly different to that of related copper boryl complexes. 相似文献
192.
Consecutive Ring Expansion and Contraction for the Synthesis of 1‐Aryl Tetrahydroisoquinolines and Tetrahydrobenzazepines from Readily Available Heterocyclic Precursors 下载免费PDF全文
Jessica E. Hill Dr. Johnathan V. Matlock Dr. Quentin Lefebvre Dr. Katie G. Cooper Prof. Jonathan Clayden 《Angewandte Chemie (International ed. in English)》2018,57(20):5788-5791
Tetrahydroisoquinolines and tetrahydrobenzazepines were prepared by acid‐promoted ring contraction of cyclic ureas, which were themselves formed by ring expansion of indolines and tetrahydroquinolines. The consequent overall one‐carbon insertion reaction gives these 6‐ and 7‐membered heterocyclic scaffolds in three steps from readily available precursors. Other ring sizes may be formed by an alternative elimination reaction of bicyclic structures. Scalability of the method was demonstrated by operating it in a flow system. 相似文献
193.
1,3—偶极环加成反应在杂螺环化合物合成中的应用 总被引:1,自引:0,他引:1
氧化腈与4,4-亚甲基-1-甲基哌啶的1,3-偶极环加成反应生成了杂螺[4.5]葵烷化合物,反应具有立体专一性.产物经LiAlH4还原生成了γ-氨基醇,最后经插入C-1单元扩环生成了新的杂螺[5.5]十一烷化合物 相似文献
194.
Anil Malik Dr. Nand Kishor Gour Sakshi Bhatt Prof. Dr. Ramesh Chandra Deka Dr. Suman L. Jain 《European journal of organic chemistry》2023,26(11):e202201338
The synthesis of 2-oxazolidinones from a three component coupling reaction of amines, epoxides, and CO2. The reaction proceeds in the presence of 1,1,3,3-tetramethylguanidine under visible light irradiation at atmospheric pressure. The optimized structures of all species involved in the reaction mechanism along with transition states have been described based on the DFT calculations. The developed methodology represents a promising approach of employing CO2 as a naturally abundant and non-toxic carbon resource to produce profitable chemicals. 相似文献
195.
O. A. Kizas A. V. Usatov P. V. Petrovskii M. G. Ezernitskaya F. M. Dolgushin A. I. Yanovsky Yu. N. Novikov A. A. Koridze 《Russian Chemical Bulletin》1998,47(9):1797-1804
The reaction of Os3(μ-Cl)2(CO)10 (1) with Ph2PCH2PPh2 (dppm) in a toluene solution at 65°C results in novel osmium complexes [Os3(μ-Cl)2(CO)9]2(dppm) (2) and [Os3(μ-Cl)2(CO)8]2(dppm)2 (3). Compounds 2 and 3 were characterized by1H and31P NMR, and IR spectroscopy and their structures were established by X-ray analysis. In both compounds, dppm is a bridging
ligand between the two cluster units. Molecule3 can be considered as an unusual 12-membered macrocycle containing C, P, Cl, and Os atoms in the ring.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1844–1851, September, 1998. 相似文献
196.
Christoph E. Strasser 《Journal of organometallic chemistry》2006,691(22):4788-4796
The first gold(I) trithiophosphite complexes were synthesised and fully characterised. Reaction of (tht)AuX (X = Cl, C6F5; tht = tetrahydrothiophene) with trithiophosphites (RS)3P (R = Me, Ph) and the bicyclic [(SCH2CH2S)PSCH2]2 (2L) afforded the corresponding molecular complexes (RS)3PAuX [R = Me, X = Cl (1); R = Me, X = C6F5 (2); R = Ph, X = Cl (3); R = Ph, X = C6F5 (4)], and 2L(AuX)2 [X = Cl (5), X = C6F5 (6)]. Reacting (tht)AuCl consecutively with two mole equivalents of (MeS)3P and then AgOTf, gave the ionic compound {[(MeS)3P]2Au}OTf (7). The compounds were characterised by multinuclear NMR spectroscopy, IR measurements and mass spectrometry, and the crystal and molecular structures of 1, 3, 6, two polymorphs of 2 as well as the known (MeO)3PAuCl (8) were determined by X-ray diffraction. The halide complexes 1 and 8 are isostructural and exhibit infinite chains of “crossed-sword”-type aurophilic interactions with Au?Au contact distances of 3.2942(3) and 3.1635(4) Å, respectively. Complex 6 exhibits a long Au?Au contact of 3.4671(9) Å. Au?S interactions between 3.3455(7) and 3.520(2) Å are present in the structures of 1 and one polymorph of 2. 相似文献
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200.
We have explored the chemistry of N-oxide heterocycles and imidazoles replacing ring D of the natural product(+)-calanolide A, and have synthesized 12 new analogues, two of which were active against both R Mtb and NR Mtb with MIC values of 12.5μg/mL, which would lead to further optimization for more potent anti-TB candidates. 相似文献