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721.
Rozbeh Yousefi 《Journal of organometallic chemistry》2005,690(1):76-78
A practical and efficient method for the synthesis of α-aminonitriles of ferrocene by one-pot three-component reaction of ferrocenecarboxaldehyde, trimethylsilyl cyanide and amines catalyzed by lithium perchlorate suspend in CH2Cl2 is reported under mild and neutral reaction conditions in high yields and short reactions times. 相似文献
722.
The frontier orbital interactions of electron pushing and drawing substituents with ferrocenyl group were analyzed based on the electrochemical,UV visible spectral and spectroelectrochemical results of five ferrocene derivatives,R-Fc-A1(PⅠ),A1-Fc-A1(PⅡ),D-Fc-R (PⅢ),D-Kc-A1(PIV) and D-Fc-A2(PV)(R,CH2OH;A1 CHO;A2,CH=C(CN)2 and D,(C18H37)2N-C6H4-CH=CH) It was found that there are strong interactions of the LUMO (πA) of electron drawing substituents with le2g(dxy,dx2 y2)and e2u of the ferroeenyl group because the energy levels of πA and e2g,C2U of (Cp )2 are close,which lower not only the energy levels of bonded orbits,πA+ and dx2-y2+[πA] of PⅠ,PⅡ,PⅣ and PⅤobviously,but also those of their non-bonded orbu dxy For PⅢ,PⅣ and PⅤ,there are strong interactions of HOMO(πD) of the electron pushing substituent with le of the ferrocenyl group because the levels of πD and e of (Cp)2 are close,which result in the formation of anti-bonded orbit,πD- and bonded orbit 相似文献
723.
MinFANG ZhiMingZHOU AiQinLUO 《中国化学快报》2005,16(6):789-792
β-Cyclodextrin 1 was directly oxidized to the corresponding monoaldehyde 2 on their primary faces by cyclized 2-iodoxybenzoic acid(IBX) in DMSO, followed by the synthesis of β-cyclodextrin derivatives bearing Schiff-base group 3. A new chiral stationary phase(BCDS 6) was then prepared by immobilization of β-cyclodextrin derivative with α-Schiff base group onto the surface of sillica gel. A series of compounds with amino groups were readily separated using this CSE Methanol and acetonitrile were tested as the mobile phase while the influence of temperature and the addition of aqueous triethylammonium acetate buffer to the mobile phase was also innvestigated. Ferrocene ligand with Schiff-based groups have been separated satisfactorilly on BCDS column. 相似文献
724.
Stability of the C21H9(MCp)
n
(n = 1—3; M = Fe, Ru) complexes containing the C21H9 radical, a representative bowl-shaped precursor of C60 fullerene, was estimated. The carbon skeleton of the radical comprises three pentagonal faces (pent). DFT calculations of the C21H9 radical and its complexes were carried out with full geometry optimization and the PBE exchange-correlation potential. The energies of the M—pent bonds were found to increase with an increase in n, being only slightly lower than those in the hypothetical icosahedral 125—-C60(MCp)12 complexes and classical sandwich complexes M(Cp)2. The increased stability of the C21H9(MCp)
n
complexes was explained by greater involvement of the conjugated system of the polyhedral skeleton in the interaction. 相似文献
725.
漆酶是含铜金属酶,主要来源于漆树漆液(生漆)和真菌,分别称漆树漆酶和真菌漆酶。近年来,人们对漆酶的催化氧化反应的研究很感兴趣。已经发现漆酶的催化反应大多在水溶液中进行,氧化底物主要是邻、对苯二酚(胺)及其衍生物,对二茂铁(Fc-H)及其衍生物(Fc-R)的催化氧化尚不多见,对共存Fc-H和K_4Fe(CN)_6的催化氧化也未见报道,这可能与Fc-H和多数Fc-R不溶于水有关。本文选择二乙二醇单丁醚(DGBE)和磷酸盐缓冲液为混合溶剂,使Fc-H和K_4Fe(CN)_6以一定浓度共溶其中,考察了在该体系中漆树漆酶对Fc-H和K_4Fe(CN)_6的催化氧化反应。 相似文献
726.
由二茂铁为起始原料合成了三个新型的二茂铁衍生物1、2、3,它们的结构都通过了核磁共振谱、红外光谱、元素分析表征。 相似文献
727.
以二茂铁为原料,经Friedel-Crafts反应合成乙酰二茂铁;并用乙酰二茂铁与乙基溴化镁反应合成2-二茂铁基-2-丁醇,产率为43%,并以IR、H1NMR确定了其结构. 相似文献
728.
用量子化学的方法对二茂铁结构进行了理论研究.采用密度泛函B3LYP方法,在6-31G (d,p)基组水平上对其进行了构型优化,振动分析.在此基础上采用GIAO方法,计算其13CNMR谱,所得结果与实验值基本吻合. 相似文献
729.
Synthesis of ferrocene‐based dipeptide receptors FcL1 , FcL2 , FcL3 , FcL4 , FcL5 was carried out by the acylation reaction of ferrocenecarboxylic acid with dipeptide esters. Compounds were characterized by IR, 1H NMR, 13C NMR and elemental analysis. Single‐crystal X‐ray analysis of FcL3 showed it has two independent chiral molecules and the two chiral atoms (C12 and C35) are in R configuration. Their cyclic voltammetric behaviors showed a pair of well‐defined and stable redox waves in the potential range 0.00–1.00 V. The configuration of the metals influenced the receptor's characteristics greatly, and at the same time the FcL compounds could selectively sense group IIB metal ions Zn2+, Cd2+ and Hg2+. The biological activities of FcL1 , FcL2 , FcL3 , FcL4 , FcL5 were studied against the tested bacteria; among them, FcL4 showed significant activity against all five bacterial strains tested. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
730.
二茂铁及其衍生物的研究状况 总被引:10,自引:0,他引:10
二茂铁的发现对金属有机化学的迅速发展起着举足轻重的作用。笔者着重探讨了近十多年来,二茂铁及衍生物的研究状况,主要从分子铁磁体、分子电子器件、非线性光学材料、接臂型大环配合物等方面进行探讨。 相似文献