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1.
以高藜芦胺为起始原料,经N-磺酰化反应制得高藜芦磺酰胺(2);2分别与芳乙烯甲醚经对甲苯磺酸催化的Pictet-Spengler反应后用金属钠脱除Ts基团合成了(±)-norlaudanosine(5a)和(±)-O,O-dimethylcoclaurine(5b);使用半量拆分法,以N-乙酰-L-苯丙氨酸为拆分剂,制得(S)-(-)-5a和(S)-(-)-5b,其结构经1H NMR,13C NMR,IR,MS和HR-ESI-MS确证。 相似文献
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《Tetrahedron letters》1986,27(38):4629-4632
Short practical syntheses are reported of the title lignans (9a) , (9c) , (13a), and (13b). 相似文献
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《Journal of Coordination Chemistry》2012,65(5):911-922
Condensation of salicyldehyde with (R or S)-2-amino-2-phenylethanol or rac-2-amino-1-phenylethanol gives enantiopure (R or S)-2-(salicylaldimine)-2-phenylethanol (R- or S-H2L1) or (rac)-2-(salicylaldimine)-1-phenylethanol (rac-H2L2). The Schiff bases coordinate to [Rh(η 4-cod)(μ-O2CCH3)]2 to afford mononuclear [Rh(η 4-cod){(R or S)-2-(salicylaldiminato)-2-phenylethanol-κ 2 N,O}], [Rh(η 4-cod)(R- or S-HL1)] (1 or 2), or [Rh(η 4-cod){(rac)-2-(salicylaldiminato)-1-phenylethanol-κ 2 N,O}], [Rh(η 4-cod)(rac-HL2)] (3). The Schiff base and complexes are characterized by IR-, UV/Vis-, 1H/13C-NMR-, mass-spectroscopy, circular dichroism (CD), and polarimetry. The synthetic and spectroscopic results suggest that deprotonated Schiff base coordinates to [Rh(η 4-cod)] as a six-membered N,O-chelate with distorted square planar geometry at rhodium. CD and polarimetry measurements show the enantiopurity of the Schiff bases as well as the complexes in solution. The in situ system composed of [Rh(η 4-cod)Cl]2 and S-H2L1 has been used as a catalyst for the reduction of acetophenone into rac-1-phenylethanol with 85% conversion in diphenylsilane at 0–5°C. 相似文献
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Introduction Asarelativelynewmemberofnaturalalkaloidswith2 ,6 disubstituted 3 piperidinolskeleton ,irnigaine 1wasisolatedfromthetubersofArisarumVulgare (Araceae)in1995byMelhaouiandBode .1Itsstructureandrelativeconfigurationswereelucidatedby1HNMRstudiesandtheabsoluteconfigurationwasproposedonthebasisofitsopti calrotation .1Soonafterthen ,Meyerandhisco workersreportedthefirstsynthesisof (- ) (2R ,3R ,6S) irni gaineandtheconfigurationconfirmation .Althoughtheirsynthesisroutewasshortan… 相似文献
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Acetalscanbesynthesizedinanumberofways.Themainproblemintheacetalformationinacidicmediumistoshifttheequilibriumtotherightbyremovalofthewaterformedduringthereactionl.Wesynthesized(2R,4S,SS)-( )-threo-5-(2,2-dich(4-nitrophenyl)-2-aryl-1,3-dioxanesbyacet... 相似文献
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《中国化学快报》1997,(5)
(R)-(-y5-[(IR,2S,5R)-menthyloxy](1)isausefulchiralsynthonreadilypreparedonatWo-stepprocedure-l']FindingsoffuranoneringsexistingascomponentSofsomenaturalproductSI'laswellastheiractivereactivityl']havestimu1atedeXtensiveresearchofitSasymmetricreactionswhichincludeDiels-Alderreactions,l']l,3-dipo1arcycloadditions,['1Michaelauditionsl5]andconjugateedditionsofaminesl']andmercaPtans.g4:,::7f:7':theseadductsledtovariousmultifunctionalhomochiralbuildingblockssuchas2-alkyl-l,4-butanediols,I'l2-aI… 相似文献
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《Journal of Coordination Chemistry》2012,65(23):4125-4136
Four new chiral triorganotin(IV) carboxylates, [(R3Sn)(O2C13H17)] n (R?=?Me 1, Ph 2), [(R3Sn)(O2C13H17)] (R?=?n-Bu 3), and [(R3Sn)(O4C9H9)] n (R?=?Me 4), have been synthesized by reaction of (S)-(+)-2-(4-isobutyl-phenyl)propionic acid and (R)-(+)-2-(4hydroxyphenoxy)propionic acid with triorganotin(IV) chloride in the presence of sodium ethoxide. The complexes have been characterized by elemental analyses, FT-IR, NMR (1H, 13C, and 119Sn) spectra, and X-ray crystallography diffraction analyses. Structural analyses show that 1 has a 1-D infinite chiral zigzag chain structure. Complexes 2 and 4 have a 1-D spring-like chiral helical chain with a channel, while 3 is a monomer. Antitumor activities of 1–4 have been studied. 相似文献
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P. Byabartta 《Russian Journal of Inorganic Chemistry》2011,56(1):44-51
Aquation of blue cis-trans-cis-[RuCl2(β-NaiR)2] (1) leads to the synthesis of solvento species, blue-violet cis-trans-cis-[Ru(OH2)2(β-NaiR)2](ClO4)2 (2), [β-NaiR = C10H7-N=N-C3H2-NN, abbreviated as N,N′-chelator, R = Me] that have been reacted with NaNO2 in warm EtOH resulting in violet dinitro complexes of the type, [Ru(NO2)2(β-NaiR)2] (3). The nitrite complexes are useful synthons of electrophilic nitrosyls, and on triturating the dinitro compounds with
cone. HClO4 nitro-nitrosyl derivatives, [Ru(NO2)(NO)(β-NaiR)2]2+ (4) are isolated. The chemical oxidation of aqua complex (2) by excess aqueous eerie solution in 1 (N) H2SO4 leads to the spontaneous formation of a yellow colored species. The electrophilic behaviour of metal bound nitrosyl has been
proved by reacting with a bicyclic ketone, camphor, containing an active methylene group and an arylhydrazone with an active
methine group. The diazotization of the primary aromatic amines with a strongly electrophilic mononitrosyl complex in acetonotrile
and dichloromethane solution was thoroughly studied. Electrocatalytic oxidation of benzyl alcohol was examined. 相似文献
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Edward Szlyk Stanislaw Biniak Erik Larsen 《Journal of Solid State Electrochemistry》2001,5(3):221-226
The electrochemical properties and catalytic activity of a Co(II) complex with the optically active Schiff base derived from
(1R,2R)-(–)-cyclohexanediamine and salicylaldehyde have been studied in non-aqueous solutions. When dissolved in deoxygenated non-aqueous
solutions, the complex exhibits reversible redox properties for the Co(II)/Co(III) couple. Electrochemical reduction of oxygen
and oxidation of cobalt(II) was observed on cyclic voltammograms of solutions containing both dioxygen and the Schiff base-cobalt(II)
complex. An anodically formed film on a platinum electrode, studied by means of X-ray photoelectron spectroscopy, revealed
the presence of the oxidized Co(III) species. Cyclic voltammetry of oxygenated solutions examined after a period of time indicates
an electrochemical activity of coordinated superoxo/peroxo species in the 0.7–1.1 V potential range. In the presence of 4-methyl-1-cyclohexene
the cyclic voltammetry curves reveal changes similar to those caused by the removal of oxygen. The GC-MS technique was used
to identify some of the products formed by the catalytic oxidation of cyclohexene and 4-methyl-1-cyclohexene.
Electronic Publication 相似文献
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The intramolecular process of Mg ( Ⅱ ) - , Sc ( Ⅲ ) - , Y ( Ⅲ ) - , In(Ⅲ)-and Pb ( Ⅱ )-trans-1,2-cyclohexanediaminetetraacetic acid (CyDTA) complexes was studied by the method of proton dynamic NMR(DNMR). The top limit of. the experimental temperature range of deuterium oxide solutions was extended from 100℃ to 167 ℃ instead of the previous 100 ℃ by using sealed, thick-walled tubes to observe experimental phenomena further. It was found that another intramolecular process, i. e. B, R (Bonded State, Rotational State) conversion, exists in these complexes formed by polyaminepolycarboxylic ligands in addition to △,A conversion and nitrogen inversion. A quantitative treatment was proposed to estimate the relative populations of acetate groups in B and R states. 相似文献
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Fullerenes C60 and C70 have high electron affinity ( 2.6 - 2.8 ev ) and readily form anions on electronchemical reduction1, which were famous as electron acceptor in photo-excitation because of symmetrical shape, large size, and properties of its p - electron system2. After observation of molecular ferromagnetism3 in the tetrakis (dimethylamino ) ethylene salt of C60 as well as the occurrence of ultra-fast photoinduced electron transfer within the dimethyl aniline - C60 complex4, prompted us… 相似文献
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Two homochiral metallosalen complexes,Ni(salen) (salen=(1R,2R)-(-)-diaminocyclohexane-N,N'-bis(3-tert-butyl-5-(4'-benzoic acid)-salicylidene) 1 and Cu(salen) 2,have been synthesized and characterized by IR,microanalysis,TGA,powder and single-crystal X-ray crystallography. Both 1 and 2 crystallize in orthorhombic space group P2_12_12 with Z=4. For 1,α= 12.082(2),b = 15.447(3),c = 18.784(4)(A),V= 3505.7(12) (A)~3,M_r = 731.50,D_c = 1.386 g/cm~3,μ= 0.606 mm~(-1),F(000)=1544,the final GOOF=1.043,R=0.0496 and wR=0.1248 for 4791 observed reflections with Ⅰ> 2σ(Ⅰ). For 2,α=12.181(2),b=15.501(3),c=18.877(4)(A),V= 3564.3(12)(A)~3,M_r=736.33,Dc = 1.372 g/cm~3,μ=0.665 mm~(-1),F(000)=1548,the final GOOF= 1.062,R=0.0575 and wR=0.1508 for 4562 observed reflections with Ⅰ> 20(Ⅰ). The crystal structures of 1 and 2 are isostructural with very similar supramolecular structures. An infinite two-dimensional network is generated by hydrogen bonding interactions and intermolecular π…π interactions. 相似文献
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The title compound methyl(E)-α-(methoxyimino)-2-((4-(3-chloro-5-(trifluoromethyl) pyridine-2-yl)phenoxy)methyl)benzeneacetate(C23 H18 ClF3 N2 O4) has been synthesized and structurally characterized by 1 H and 13 C NMR, and HRMS. Its absolute molecular configuration was investigated by X-ray crystallography. The crystal crystallizes in monoclinic system, space group P21/c with a = 15.0928(7), b = 19.6070(10), c = 7.5535(5) ?, β = 98.176(5)°, V = 2212.6(2) ?3, Z =4, Dc = 1.438 g/cm3, F(000) = 984, μ(Mo Kα) = 0.231 mm-1, the final R = 0.0619 and wR = 0.1681 with 4034 observed reflections with I 2σ(I). The title compound has significant inhibitory rate against broadleaf weeds. They are all 100% under the dose of 37.5 g.a.i/ha, which was better than mesotrione. 相似文献
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Yurii Slyvka Evgeny Goreshnik Gleb Veryasov Dmitry Morozov Andrii A. Fedorchuk Nazariy Pokhodylo 《Journal of Coordination Chemistry》2019,72(5-7):1049-1063
The present work is directed toward preparation, structure and optical property characterization of tetrazole-containing Cu(I) compounds. By means of the alternating-current electrochemical technique copper(I) π,σ-compounds with 1-(4-methylphenyl)- (Matht), 1-(3-chloro-4-methylphenyl)- (Chmatht) and 1-[2-(trifluoromethyl)phenyl]- (Tfmatht) 5-(allylthio)-1H-tetrazoles were obtained in a single crystal form and structurally characterized by X-ray diffraction and Raman spectroscopy. Matht and Chmatht ligands, being attached to the Cu(I) through S-allylic C?=?C-bond and two tetrazole N-atoms, form stable centrosymmetric dimers [Cu2(Matht)2(H2O)2](BF4)2 and [Cu2(Chmatht)2(СlO4)2]. The presence of an electron acceptor trifluoromethyl group promotes formation of the monomeric [Cu(Tfmatht)2]BF4 and [Cu(Tfmatht)(NH2SO3)(MeOH)] compounds. The compounds were investigated by means of Raman spectroscopy, third-order nonlinear optics and DFT calculations. 相似文献
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《Polyhedron》2002,21(27-28):2711-2717
Schiff bases obtained from N,N′-(1R,2R)-1,2-cyclohexanediamine and 2-hydroxy-3-methylbenzaldehyde, 2-hydroxy-5-methylbenzaldehyde, have been used as ligands for copper(II), cobalt(II) and nickel(II). The complexes were characterized with UV–Vis, circular dichroism (CD), infrared, diamagnetic and paramagnetic 1H NMR spectroscopy. CD spectra revealed exciton coupled π→π* transitions. Assignments of LMCT and d–d transitions in CD spectra of Ni(II), Co(II) and Cu(II) complexes is proposed. CD data are characteristic for central ion tetrahedral distortion from the planarity and λ conformation of the cyclohexane ring. 1H NMR of Ni(II) complexes exhibited significant coordination shifts of CHN and ring protons which are in the closest proximity to Ni(II). The 1H NMR paramagnetic spectra of Co(II) complexes revealed the most upfield shifted resonance at −60 ppm assigned to CHN and −28 ppm to hydrogen atom at C(5′) of the phenyl ring. Results of spectral analyses suggest central ions in a distorted square-planar geometry with N2O2 chromofore group. 相似文献