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1.
Howard Alper 《Journal of organometallic chemistry》1975,96(1):95-98
(N-Carboalkoxy-1,2-dihydropyridine)iron tricarbonyl complexes have been isolated by treatment of either N-carboalkoxy-1,2 or -1,4-dihydropyridines with diiron ennecarbonyl. The organic ligand was liberated from these complexes by use of trimethylamine oxide. 相似文献
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Acylation of diene Fe(CO)3 complexes using the Perrier complexes RCOCl/AlCl3 in methylene chloride at 0°C gives dienone complexes in high yield. Substitution occurs only at unsubstituted terminal carbons of the diene unit. Quenching the reaction mixtures in cold aqueous ammonia gives cis dienone complexes only. Trans dienone complexes are prepared by subsequent isomerization in methanolic sodium methoxide. Formylation of diene Fe(CO)3 complexes proceeds in modest yield using dichloromethylmethyleter/AlCl3 in methylene chloride to give trans-dienal complexes. Reduction of the dienone and dienal complexes as well as those of dienols and dienoic esters with 4 : 1 AlCl3/LiAlH4 results in complete removal of the oxygen function to give trans-diene complexes in good yield. 相似文献
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Synthesis of S2Fe2(CO)6 and S2Fe3(CO)9 by direct substitution of the carbonyl ligands in iron carbonyls with sulfur is described. The relative reactivities were determined for both iron carbonyls and organosulfur compounds in reactions of R2S, R2S2 and RSH (R = alkyl, aryl) with Fe(CO)5, Fe2(CO)9 and Fe3(CO)12. The properties of the [RSFe(CO)3]2 obtained are studied. New methods are found for their regeneration in the form of sulfides, disulfides and thiols. 相似文献
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Complexed cyclopropyl-3,4-dihydroxyphenylalanine (∇ DOPA) were synthesized by diazomethane cyclopropanation of the appropriate diene(tricarbonyl)iron complexes linked to azlactones. Opening of the oxazolone ring by treatment with MeOH and DMAP gave the corresponding methyl esters. Introduction of the Boc group, cleavage of the carbamate with hydrazine provided Boc-protected cyclopropylogs of dl-dihydroxyphenylalanine. 相似文献
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X-substituded benzamides (X = H; 2-OH; 4-MeO; 3-MeO; 3,5-(MeO)2; 4-Cl and 2,4-Cl2) have been shown to add reversibly to the dienyl rings of the organometallic compounds [(dienyl)Fe(CO)3]BF4 (dienyl = C6H7, 2-MeOC6H6 or C7H9) to give the corresponding cationic tricarbonyl(substituted-diene)iron complexes. 相似文献
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《Tetrahedron: Asymmetry》2000,11(15):3091-3102
Addition of allyldiisopinocampheylborane to racemic (dienal)iron complexes, followed by oxidation, affords diastereomeric (1,4,6-trien-3-ol)iron complexes with moderate to low enantioselectivity. The high enantioselectivity typically observed for this allylborane reagent is attenuated by steric interaction between the Fe(CO)3 group and the chiral isopinocampheyl groups. Further diminution of the enantioselectivity is observed for dienal complexes in which one rotomer predominates. 相似文献
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Naoya Harada Masahiro Ono Yoshiro Ohmomo Hidekazu Kawashima 《Journal of organometallic chemistry》2011,696(23):3745-3749
Technetium-99m (99mTc) is one of the most frequently used nuclides for single-photon emission computed tomography (SPECT) imaging because of its radiochemical characteristics, such as gamma emission of suitable energy (141 keV) and adequate half-life (6.01 h). Although triaquatricarbonyl 99mTc cation ([99mTc(CO)3(H2O)3]+) has several advantages as a 99mTc-labeling agent, e.g., compact chelate size, chelate stability, and simplicity of preparation, its synthetic protocols should be improved. Because microwave heating is a convenient method for synthetic reactions, we studied the effect of microwave irradiation on the synthesis of 99mTc tricarbonyl complexes. We found several factors beneficial for the preparation of nuclear medicines. In particular, microwave heating promoted one-pot syntheses of 99mTc tricarbonyl chelates in a short time. In addition, the 99mTc tricarbonyl complex could be obtained using low concentrations of ligands. 相似文献
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2,3-Homotroponeiron tricarbonyl, 8-methyl- and 8,8-dimethyl-2,3-homotroponeiron tricarbonyl complexes have been shown to undergo O-protonation in trifluoroacetic (TFA) and 96% sulfuric acids. In the latter acid the O-protonated cations rearrange to give the thermodynamically more stable C-protonated isomers. Cyclooctatrienoneiron tricarbonyl undergoes protonation H2SO4 to give the same cation as was obtained from the protonation of the homotroponeiron tricarbonyl complex in H2SO4. On the basis of reaction in D2SO4, it is suggested that the kinetically preferred site of protonation of the cyclooctatrienone complex is at C(2) one of the coordinated carbon atoms. 相似文献
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A. I. Rezvukhin V. N. Piottukh-Peletskii R. N. Berezina V. G. Shubin 《Russian Chemical Bulletin》1973,22(3):694-696
Conclusions The13C NMR spectroscopy data obtained for the iron tricarbonyl complexes of the benzolonium ions are in agreement with the postulate that the iron tricarbonyl fragment takes an effective part in a delocalization of the positive charge.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 3, pp. 705–707, March, 1973. 相似文献
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Brian F.G. Johnson Jack Lewis David G. Parker G.Richard Stephenson 《Journal of organometallic chemistry》1980,197(1):67-75
Tricarbonyl(cyclohexadiene)iron(0) complexes bearing olefinic side-chains at the 2- or the 5-position have been prepared by a versatile route. Terminal olefins are isomerised to internal isomers. The presence of a methoxy substituent at the 2-position prevents isomerisation of the coordinated diene into conjugation with the olefin, so locking the side-chain at the 5-exo-position. 相似文献
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M. Rute G. da Costa M. João M. Curto Stephen G. Davies Fátima C. Teixeira James E. Thomson 《Tetrahedron》2018,74(40):5965-5973
(Aryl aldehyde)- and (aryl ketone)-chromium tricarbonyl complexes ortho-substituted with the chiral auxiliary O-methyl-N-(α-methylbenzyl)hydroxylamine undergo diastereoselective addition of Grignard reagents and Super-Hydride®, respectively, to give the corresponding secondary alcohols in high diastereoisomeric purity. These compounds may be easily decomplexed and deprotected to give the corresponding enantiopure amino alcohols. 相似文献
19.
Ambroz Almssy Zuzana Benkov Branislav Horvth Andrej Boh
《Journal of organometallic chemistry》2008,693(20):3223-3232
The compositions of regioisomeric mixtures of tricarbonyliron complexes of 2-methyltropone (1a,b), 3-methyltropone (2a,b) and 2,6-dimethyltropone (3a,b) are studied and compared with the results of ab initio computations. The structures, frontier orbitals, and population analysis are evaluated by means of density functional theory. The thermodynamic and kinetic parameters of regioisomerizations are determined using dynamic 1H NMR technique. The influence of methyl-substituent(s) on the equilibrium ratio of regioisomers resulting from the haptotropic rearrangement is discussed. Significant differences in the reactivity of C-protonized methyl- and dimethyl-substituted tricarbonyl(tropone)iron complexes 4–6 in nucleophilic additions and corresponding O-trimethylsilylated complexes 7–9 in [3+2] cycloadditions are explained in terms of electronic and steric effects of the methyl group(s). Various hydroazulenone cycloadducts of tricarbonyl(η4-2,6-dimethyltropone)iron 3a,b have been prepared by stereoselective [3+2] cycloaddition with Fp-reagents 12–14 and characterized. Formerly proposed mechanism of [3+2] cycloaddition was approved. 相似文献