1-Phenyl-5(6)-methyldihydrouracils and their transformations

The reaction of aniline with methacrylic and crotonic acids gave N-phenyl-- or -methyl--alanines, which were converted to the corresponding 1-phenyl-5(6)-methyl- and 1-phenyl-2-thioxo-5(6)-methyldihydrouracils by the action of urea or thiocyanates in an acidic medium. The dihydrouracils were converted to ureido acids by the action of alkalis and to N-phenyl--alanine hydrazides by the action of hydrazine. 1-Phenyl-2-thioxo-5-methylhexahydropyrimidine was isolated in the reduction of the thioxodihydrouracil. The dihydro- and thioxodihydrouracils react with phosphorus pentasulfide to give 4-thioxo- and 2,4-dithioxodihydrouracils. 1-Phenyl-5(6)-methyldihydrocytosines were obtained from the 4-thioxodihydrouracils. The thioxodihydrouracils were subjected to bromination; 1-(4-bromophenyl)-5(6)-methyldihydrouracils were obtained from 1-phenyl-5(6)-methyldihydrouracils, and 1-phenyl-2-thioxo-5-bromo-5-methyldihydrouracil, which was converted to a uracil by dehydrobromination, was obtained from 1-phenyl-2-thioxo-5-methyldihydrouracil. 1-Phenyl-2-thioxo-5-methyluracil was also obtained by dehydrogenation of 1-phenyl-2-thioxo-5-methyldihydrouracil with sulfur.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1097–1101, August, 1981.     

Synthesis,structure, and dissociation equilibrium of [Co(eta5-C5H5)(Se2C6H4)]2, a novel metalladiselenolene complex

A (phenylenediselenolato)cobalt complex dimer, [Co(eta(5)-C(5)H(5))(Se(2)C(6)H(4))](2) (1), was synthesized by a reaction of carbonyl(eta(5)-cyclopentadienyl)diiodocobalt(III) ([Co(eta(5)-C(5)H(5))I(2)(CO)]) with poly(o-diselenobenzene). The structure of 1, determined by single-crystal X-ray crystallography, was found to be located in the space group of P2(1)/c (No. 14), with a = 9.3346(5) A, b = 11.6477(9) A, c = 10.2179(5) A, beta = 111.491(1) degrees, and Z = 2. Covalent Co-Se bonds bridge the metal centers. In solution, dimers and monomers coexist at equilibrium. The dissociation equilibrium constant of 1 in solution was evaluated by (1)H NMR spectra at several temperatures between 20 and 80 degrees C. Dissociation enthalpies/entropies were found to be 50/110, 60/120, and 88 kJ mol(-1)/200 J K(-1) mol(-1) in dimethyl sulfoxide-d(6), benzene-d(6), and chloroform-d(1), respectively.     

键联环糊精、糖苷的卟啉及金属卟啉的合成

全甲基化-6-羟基-β-环糊精(PMβ-CD-CH₂OH)在N₂气流下与三氟甲基磺酸酐反应得到全甲基化-6-三氟甲基磺酸酯-β-环糊精(PMβ-CD-CH₂OTf)(6).6分别与5-(p-氨基苯基)-10,15,20-三苯基镍(钌羰基)卟啉[NiTP_NH2P](2)和[Ru(CO)TP_NH2P](3)缩合得到化合物7和8.1-溴-2,3,4,6-O-乙酰基-α-D-葡萄糖(4)和1-溴-2,3,5-O-乙酰-β-D-呋喃糖(5)分别与H₂TP_NH2P(1)反应得到化合物9和10.新化合物6-10经IR,UV-Vis,¹HNMR和元素分析确证,其中化合物6由MS谱进一步确定.     

Facile access to redox-active C2-bridged complexes with half-sandwich manganese end groups

The dinuclear mixed-valent complex [(MeC5H4)(dmpe)MnC(2)Mn(dmpe)(C5H4Me)](+)[(eta2-MeC5H4)3Mn](-)[1](+)[2]- (dmpe=1,2-bis(dimethylphosphanyl)ethane) was prepared by the reaction of [Mn(MeC5H4)2] with dmpe and Me(3)SnC[triple chemical bond]CSnMe3. The reactions of [1](+)[2]- with K[PF6] and Na[BPh4] yielded the corresponding anion metathesis products [(MeC5H4)(dmpe)MnC2Mn(dmpe)(C5H4Me)][PF6] ([1][PF6]) and [(MeC5H4)(dmpe)MnC2Mn(dmpe)(C5H4Me)][BPh4] ([1][BPh4]). These mixed-valent species can be reduced to the neutral form by reaction with Na/Hg. The obtained complex [(MeC5H4)(dmpe)MnC2Mn(dmpe)(C5H4Me)] (1) displays a triplet/singlet spin equilibrium in solution and in the solid state, which was additionally studied by DFT calculations. The diamagnetic dicationic species [(MeC5H4)(dmpe)MnC2Mn(dmpe)(C5H4Me)][PF6]2 ([1][PF6]2) was obtained by oxidizing the mixed-valent complex [1][PF6] with one equivalent of [Fe(C5H5)2][PF6]. Both redox processes are fully reversible. The dinuclear compounds were characterized by NMR, IR, UV-visible, and Raman spectroscopy, cyclic voltammetry, and magnetic susceptibility measurements. X-ray diffraction studies were performed on [1][2], [1][PF6], [1][BPh4], and [1][PF6]2.     

Synthesis, characterization, and reactivity of [Li(N6,N9-Me2Ade(-H))]: a structurally characterized lithiated adenine

The reaction of N6,N9-dimethyladenine (N6,N9-Me2Ade, 1) with methyllithium in aprotic solvents such as tetrahydrofuran and pyridine resulted in the formation of the lithiated adenine [Li(N6,N9-Me2Ade-H)] (2) that was isolated as highly air and moisture sensitive tetrahydrofuran (2.(1/4)THF) and pyridine (2.py) adducts in excellent yields (>90%). The identities of 2.(1/4)THF and 2.py were confirmed by 1H and 13C NMR spectroscopy. In crystals of 2.(3/2)py, the dimethyladeninato ligand exhibited a chelating and bridging coordination mode (kappa2N6,N7:kappaN3) resulting in a 1-D polymeric chain-like structure in which the tetrahedral coordination sphere of the lithium atoms was completed by a pyridine molecule. Reactions of 2.(1/4)THF with electrophiles such as MeI, Me3SiCl, and Me3SnCl resulted in high yields (88-98%) of the formation of the adenine deriatives N6,N6,N9-Me3Ade-H (3), N6-(SiMe3)-N6,N9-Me2Ade(-H) (4), and N6-(SnMe3)-N6,N9-Me2Ade-H (5), respectively. Compounds 3-5 were characterized by 1H, 13C, 29Si (4), and 119Sn (5) NMR spectroscopy and MS investigations, and the stannylated derivative 5 also was characterized by single-crystal diffraction analysis exhibiting a mononuclear structure. The reaction of the stannylated adenine 5 with n-BuLi in n-hexane proceeded in the sense of a tin-lithium transmetalation reaction yielding the solvent-free lithium adeninate [Li(N6,N9-Me2Ade-H)] (2) in 90% yield.     

Synergic Extraction of Uranium Thiocyanate by the Ternary System of ABC Species Composed of PMBP-TBP-(C6H5)4AsCI

The synergic extraction of uranyl thiocyanate with binary system of 1-phenyl-3-methy1~4-benzoylpyrazolone-5 (PMBP)and tributyl phosphate(TBP)or tetraphenylarsonium chloride [(C6H5)4AsCl] and ternary system of PMBP-TBP-(C6H5 )4AsCl was studied.There was an obvious synergic effect of uranium (VI)from thiocyanate medium in binary and ternary systems.The formation of a ternary extracted complex,(C6H5)4AsUO2.(NCS)A2 TBP,was confirmed by the slope method.A method was first proposed for the calculation of the equilibrium constant of ternary synergic reaction.     

Chemical and electrochemical oxidation of thiophene-pyridine and thiophene-pyrimidine co-oligomers in solutions

Chemical and electrochemical oxidation (or p-doping) of three types of pi-conjugated co-oligomers, Py-Th-(Th)n-Th-Py (Py = pyridine unit; Th = thiophene unit; 5a, n = 1; 6a, n = 2), Th-Py-(Th)n-Py-Th (5b: n = 1; 6b: n = 2), and Pym-Th-(Th)n-Th-Pym (Pym = pyrimidine unit; 5c: n = 1; 6c: n = 2), in solution systems has been studied. The chemical oxidation with NOBF(4) proceeded with isosbestic points in the UV-vis spectrum. The UV-vis absorption peak of 5a at 418 nm in CH(2)Cl(2) shifted to 456 nm after oxidation of 5a with NOBF(4). The oxidized 5a was easily reduced by N(2)H(4) to give the original UV-vis spectrum of 5a, and 5b, 6b, and 5c behaved similarly in the oxidation and reduction. In the oxidation by NOBF4, an (oxidized co-oligomer)/(original neutral co-oligomer) ratio of 1 was attained at [NOBF4] = 1.3 x 10(-6), 4 x 10(-6), 7 x 10(-6), and 9 x 10(-6) M for 5a, 6b, 5b, and 5c, respectively. The obtained data are considered to reflect the ease of oxidation of the co-oligomer, which is affected by the electron-accepting nature of the N-containing aromatic unit in the co-oligomer and effective pi-conjugated length of the co-oligomer. The cyclic voltammogram of 5a showed three redox couples with anodic peak current potentials of Epa = 0.75, 1.10, and 1.34 V versus Ag+/Ag, respectively. The first oxidation peak was assigned to one-electron oxidation of 5a, and electronic current of the first anodic peak (i) of 5a and 5c was proportional to (scanning rate)1/2. From the i- (scanning rate)1/2 relationship, diffusion constants, D's, of 5a and 5c were estimated to be 9.6 x 10(-6) and 1.7 x 10(-5) cm2 s(-1), respectively. CV data of 5b with the terminal thiophene units indicated occurrence of electrochemical oxidative polymerization of 5b.     

Total Synthesis of Talatisamine

Talatisamine ( 1 ) is a member of the C₁₉‐diterpenoid alkaloid family, and exhibits K⁺ channel inhibitory and antiarrhythmic activities. The formidable synthetic challenge that 1 presents is due to its highly oxidized and intricately fused hexacyclic 6/7/5/6/6/5‐membered‐ring structure (ABCDEF‐ring) with 12 contiguous stereocenters. Here we report an efficient synthetic route to 1 by the assembly of two structurally simple fragments, chiral 6/6‐membered AE‐ring 7 and aromatic 6‐membered D‐ring 6 . AE‐ring 7 was constructed from 2‐cyclohexenone ( 8 ) through fusing an N‐ethylpiperidine ring by a double Mannich reaction. After coupling 6 with 7 , an oxidative dearomatization/Diels–Alder reaction sequence generated fused pentacycle 4 b . The newly formed 6/6‐membered ring system was then stereospecifically reorganized into the 7/5‐membered BC‐ring of 3 via a Wagner–Meerwein rearrangement. Finally, Hg(OAc)₂ induced an oxidative aza‐Prins cyclization of 2 , thereby forging the remaining 5‐membered F‐ring. The total synthesis of 1 was thus accomplished by optimizing and orchestrating 33 transformations from 8 .     

Asperflavipine A: A Cytochalasan Heterotetramer Uniquely Defined by a Highly Complex Tetradecacyclic Ring System from Aspergillus flavipes QCS12

Asperflavipines A ( 1 ) and B ( 2 ), two structurally complex merocytochalasans, were isolated from Aspergillus flavipes . Asperflavipine A ( 1 ), which contains two cytochalasan moieties and two epicoccine moieties, is the first cytochalasan heterotetramer to be discovered. It is uniquely defined by 5/6/11/5/6/5/6/5/6/5/5/11/6/5 fused tetradecacyclic rings with three continuous bridged ring systems. Asperflavipine B ( 2 ) is a cytochalasan heterotrimer containing a cytochalasan and two epicoccine moieties with a 5/6/11/5/5/6/5/6/5 nonacyclic ring system. The hypothetical biosynthesis of 1 and 2 is proposed to involve Diels–Alder and [3+2] cycloaddition reactions as key steps and reveals unparalleled plasticity in the biosynthesis of merocytochalasans. The existence of 1 adds a new dimension to the diversity of the cytochalasan family. Compound 1 showed moderate cytotoxicity and induced apoptosis in Jurkat, NB4, and HL60 cells through the activation of caspase‐3 and degradation of poly(ADP‐ribose) polymerase (PARP).     

Synthesis and In Vivo antitumor and antiviral activities of 2′-deoxyribofuranosyl and arabinofuranosyl nucleosides of certain purine-6-sulfenamides,sulfinamides and sulfonamides

2′-Deoxyribofuranosyl and arabinofuranosyl nucleosides of certain purine-6-sulfenamides, sulfinamides and sulfonamides have been prepared by sequential amination and controlled oxidation of the corresponding 6-thiopurine nucleosides, and evaluated for antiviral and antitumor activities in mice. Amination of 2′-deoxy-6-thioinosine ( 4a ) and 9-β-D-arabinofuranosyl-6-thiopurine ( 4c ) with chloramine solution gave the corresponding 6-sulfenamides 5a and 5c , respectively, which on selective oxidation with 3-chloroperoxybenzoic acid (MCPBA) gave diastereomeric 9-(2-deoxy-β-D-erythro-pentofuranosyl)purine-6-sulfinamide ( 6a ) and 9-β-D-arabinofuranosylpurine-6-sulfinamide ( 6c ), respectively. However, oxidation of 5a and 5c with excess of MCPBA gave the corresponding 6-sulfonamide derivatives 7a and 7c , respectively. Similar amination of 2′-deoxy-6-thioguanosine ( 4b ), ara-6-thioguanine ( 4d ) and α-2′-deoxy-6-thioguanosine ( 8 ) gave the respective 6-sulfenamide derivatives 5b, 5d and 9 . Controlled oxidation of 5b, 5d and 9 gave (R,S)-2-amino-9-(2-deoxy-β-D-erythro-pentofuranosyl)purine-6-sulfinamide ( 6b ), (R,S)-2-amino-9-β-D-arabinofuranosylpurine-6-sulfinamide ( 6d ) and the α-anomer of ( 6b) (10 ), respectively. The diastereomeric mixture of (R,S )-10 was partially resolved and the structure of S -10 was assigned by single-crystal X-ray diffraction analysis. Oxidation of 5b, 5d and 9 with excess of MCPBA afforded the respective 6-sulfonamide derivatives 7b, 7d and 11 . Nucleosides 5c and 7c were significantly active against Friend leukemia virus in mice, whereas 6c was somewhat less active. Of the 20 nucleosides evaluated, 12 exhibited biologically significant anti-L1210 activity in mice. Nucleosides 6b and 7a at 173 mg/kg/day × 1 showed a T/C of 153, whereas 7d at 800 mg/kg/day × 1 showed a T/C of 153 against L1210 leukemia. The α-nucleoside 9 at 480 mg/kg/day × 1 gave a T/C of 172. A single treatment with 6b, 7a, 7d and 9 reduced the body burdens of viable L1210 cells by more than 99.2%. The antileukemic activity of these novel nucleosides tended to parallel solubility.     

三(三甲基硅)环戊二烯与六羰基钼的反应

三(三甲基硅)环戊二烯与六羰基钼在二甲苯中回流8h,反应停留在生成中间物η⁵-[(Me₃Si)_NC₅H_5-n]Mo(CO)₃H(n=2,3)(I)的阶段.不经分离,I随即分别与CCl₄·NBS及MeI反应,生成其相应的钼卤化物η-⁵[(Me₃Si)_NC₅H_5-n]Mo(CO)₃X[n=3,X=Cl(1),Br(2),I(3);n=2,X=Cl(4),Br(5),I(6)].4-6是由于茂环上脱掉1个Me₃Si基.经元素分析和IR及¹H NMR谱表征了化合物1-6的结构,并用X射线衍射测定了1的晶体结构.     

新型含1,2,3-三氮唑的染料木素糖缀合物的合成

以染料木素为起始原料,经两步反应制得中间体7-O-炔丙基染料木素(3);以CuI为催化剂,3与叠氮乙酰基糖经Click反应合成了7-O-［1-(2,3,4,6-四-O-乙酰基-β-D-糖苷)1H-1,2,3-三氮唑-4-甲基］-染料木素(5a~5c); 5a~5c经去乙酰基制得三种含1,2,3-三氮唑的氮苷染料木素糖缀合物(6a~6c)。3, 5和6均为新化合物,其结构经¹H NMR, ¹³C NMR和HR-MS表征。     

Preparative isolation and purification of five compounds from the Chinese medicinal herb Polygonum cuspidatum Sieb. et Zucc by high-speed counter-current chromatography

High-speed counter-current chromatography (HSCCC) was applied to the separation and purification of five compounds from the Chinese medicinal herb Polygonum cuspidatum Sieb. et Zucc. The crude extracts from P. cuspidatum Sieb. et Zucc were treated with light petroleum-ethyl acetate-methanol-water (2:5:4:6, v/v). Sample 1 was obtained from the lower phase and sample 2 from the upper phase. The sample 1 was separated with light petroleum-ethyl acetate-water (1:5:5, v/v) and yielded 19.3mg of piceid, 17.6 mg of anthraglycoside B from 200mg of sample 1. The sample 2 was separated with light petroleum-ethyl acetate-methanol-water (3:5:4:6, v/v) and light petroleum-ethyl acetate-methanol-water (3:5:7:3, v/v) in a gradient elution and yielded 18.5mg of resveratrol, 35.3mg of emodin and 8.2mg of physcion from 220 mg of sample 2. The purity of each compound is over 95% as determined by HPLC. The chemical structures of these components were identified by (1)H NMR and (13)C NMR.     

Synthesis and Structural Characterization of [Cu(DMF)_6][(η~5-C_5Me_5)WS_3(CuBr)_3]_2·Et_2O

1 INTRODUCTION In the last decade, we have been interested in the synthesis of [PPh4][(h5-C5Me5)MS3] (M = Mo, W)[1, 2] , Whose organometallic trisulfido anions show high reactivity towards various transition metals[3~6] . We once reported that the reaction of [PPh4][(h5-C5Me5)WS3] with CuBr in CH3CN afforded a double incomplete-cubane cluster [PPh4]2[(h5-C5Me5)WS3(CuBr)3]2[3], while the analogous reaction of [PPh4][(h5-C5Me5)WS3] with CuBr in CHCl3 gave rise to a 揻our-…     

Phosphorus–nitrogen compounds. Part VI. Aminolysis of octachlorocyclotetraphosphazatetraene and the crystal structure of 2-trans-6-bis(n-propylamino)-2,4,4,6,8,8-hexakis-tert-butylaminocyclo-2λ, 4λ, 6λ, 8λ-tetraphosphazatetraene

The reactions of 2-trans-6-N₄P₄(NHPrⁿ)₂Cl₆ (2), which was obtained from N₄P₄Cl₈ (1) and n-propylamine, with pyrrolidine and t-butylamine in different solvents have been studied. Compound (2) gave two different products, namely monocyclic (3 and 5) and bicyclic (4 and 6) phosphazenes. Compounds (2–6) have been characterized by elemental analysis, IR, ¹H-, ¹³C-, ³¹P NMR, HETCOR and MS and the structure of compound (5) has been examined crystallographically. The bicyclic phosphazene (6) is the first exciting example of bicyclic phosphazenes containing chlorine atoms, in the literature. The formation mechanisms of bicyclic phosphazenes are re-considered by taking into account the synthesis of compound (6), which contains three stereogenic phosphorus atoms. Compound (5) crystallizes in the monocyclic space group P2₁/n with a=13.974(2), b=17.836(5), and c=18.683(4) Å, β=98.50(1)°, V=4605.4(2) Å³, Z=4 and D_x=1.051 g cm^−3. It consists of a non-centrosymmetric, non-planar phosphazene ring in a saddle conformation, with two n-propylamino (in 2-trans-6 positions) and six bulky t-butylamino side groups. The bulky substituents are instrumental in determining the molecular geometry.     

Synthesis, characterization, and X-ray crystal structures of W(VI) alkyl complexes with chelating diamide and imido co-ligands

The complex W(NPh)Cl₂[o-(NSiMe₃)₂C₆H₄] 3 was synthesized from PhN = WCl₄ · OEt₂ and N,N′-(Li₂[o-(NSiMe₃)₂C₆H₄] and reacts with Lewis bases to form the adducts W(NPh)Cl₂[o-(NSiMe₃)₂C₆H₄](L) (L = PMe₃, THF, 3-picoline, ^tBuNC, MeCN) 4a–e. Crystals of 4a are triclinic, space group P1¯, with a = 9.562(1), b = 10.277(1), c = 14.920(2) Å, = 82.15(1), β = 80.18(1), γ = 80.41(1)°, and Z = 2. The structure was solved by the heavy atom method and refined to R = 0.0408 for 4224 observed (I > 2σ(I)) reflections. The dialkyl complexes W(NPh)R₂[o-(NSiMe₃)₂C₆H₄] (R = Me, Et, CH₂Ph, CH₂CMe₃, CH₂CMe₂Ph) 5–9 are formed through subsequent reactions of 3 with the corresponding Grignard reagent. Crystals of complex 5 are monoclinic, space group P2(1)/n, with a = 10.3545(2), b = 17.9669(1), c = 13.3168(1) Å, β = 103.826(1)°, and Z = 4. The structure of complex 5 was solved by direct methods in SHELXTL5 and refined to R = 0.0247 for 4572 observed reflections. Compound 5 has a square pyramidal geometry in which the imido ligand occupies the apical position and reacts with PMe₃ to form the adduct W(NPh)Me₂[o-(NSiMe₃)₂C₆H₄](PMe₃) 5a. Crystals of complex 5a are monoclinic, space group C2/m, with a = 13.5336(1), b = 14.4291(1), c = 15.3785(1) Å, β = 110.365(1)°, and Z = 4. The structure of compound 5a was solved by direct methods in shelxtl5 and refined to R = 0.0272 for 3057 observed reflections. Crystals of the bis-neopentyl complex 8 are monoclinic, space group P2(1)/n, with a = 10.6992(4), b = 18.3144(7), c = 16.0726(6) Å, β = 92.042(1)°, and Z = 4. The structure of 8 was solved by direct methods in shelxtl5 and refined to R = 0.0261 for 5881 observed reflections. Complex 8 has a trigonal bipyramidal geometry with both neopentyl groups and one amido nitrogen in the equatorial plane.     

Infrared absorption of gaseous benzoyl radical C6H5CO recorded with a step-scan Fourier-transform spectrometer

A step-scan Fourier-transform infrared spectrometer coupled with a multipass absorption cell was utilized to monitor the gaseous transient species benzoyl radical, C(6)H(5)CO. C(6)H(5)CO was produced either from photolysis of acetophenone, C(6)H(5)C(O)CH(3), at 248 nm or in reactions of phenyl radical (C(6)H(5)) with CO; C(6)H(5) was produced on photolysis of C(6)H(5)Br at 248 nm. One intense band at 1838 ± 1 cm(-1), one weak band at 1131 ± 3 cm(-1), and two extremely weak bands at 1438 ± 5 and 1590 ± 10 cm(-1) are assigned to the C═O stretching (ν(6)), the C-C stretching mixed with C-H deformation (ν(15)), the out-of-phase C(1)C(2)C(3)/C(5)C(6)C(1) symmetric stretching (ν(10)), and the in-phase C(1)C(2)C(3)/C(4)C(5)C(6) antisymmetric stretching (ν(7)) modes of C(6)H(5)CO, respectively. These observed vibrational wavenumbers and relative IR intensities agree with those reported for C(6)H(5)CO isolated in solid Ar and with values predicted for C(6)H(5)CO with the B3LYP/aug-cc-pVDZ method. The rotational contours of the two bands near 1838 and 1131 cm(-1) simulated according to rotational parameters predicted with the B3LYP/aug-cc-pVDZ method fit satisfactorily with the experimental results. Additional products BrCO, C(6)H(5)C(O)Br, and C(6)H(5)C(O)C(6)H(5) were identified in the C(6)H(5)Br/CO/N(2) experiments; the kinetics involving C(6)H(5)CO and C(6)H(5)C(O)Br are discussed.     

Schinarisanlactone A, a new bisnortriterpenoid from Schisandra arisanensis

A novel triterpenoid, schinarisanlactone A (1), was isolated from the fruits of Schisandra arisanensis. Compound 1 possesses an unprecedented skeleton having a 5/7/7/5/7/5/6/5-fused octacyclic ring system. The structure of 1 was determined by 2D NMR techniques (COSY, HMQC, HMBC, and NOESY) and was confirmed by X-ray crystallographic analysis. Schinarisanlactone A (1) exhibited significant anti-HIV activity.     

5-硝基-2H-四唑的合成、反应性及产物晶体结构的研究

5-氨基四唑(1)经过重氮化反应得到5-硝基四唑(5),5与甲醛反应得到2-羟甲基-5-硝基四唑(6),6与HCl或HBr反应分别得到5-5氯代四唑(7)和5-溴代四唑(8),采用MS,IR,1H NMR,13C NMR等技术对这些化合物进行了表征.用X射线单晶衍射法测定了化合物5-硝基四唑钠(4),5和6的晶体结构.化合物4属于三斜晶系,P-1空间群;化合物5和6均属于单斜晶系,P21空间群,化合物6的晶胞参数a=0.66131(18)nm,b=0.54905(15)nm,c=0.7566(2)nm,Z=2,V=0.27470(13)nm3,Dc=1.754g/cm3,F(000)=128,μ=0.160mm-1.     

层状纳米光催化复合材料HNbWO6/Pt的合成及性质

用固相合成法合成出LiNbWO6,并用离子交换法制备出HNbWO6;通过PrNH2 层间膨胀、Pt(NH3 ) 2 + 4层间插入和紫外光分解等反应 ,合成出一种新的层状光催化纳米复合材料HNbWO6/Pt ,并比较了不同合成方法对样品性能的影响 .X射线衍射、漫反射、ICP和比表面积测定等的表征结果表明 :该样品的层间高度为 0 .3～ 0 .5nm ,禁带能隙为 2 .2 5～ 3.10eV .用波长大于 2 90nm的 45 0W汞灯照射 5h ,1g样品可催化分解甲醇溶液 (10 % )产生氢气约 40ml,表明所研制的层状纳米复合材料具有较高的光催化活性