莽吉柿中几种双苯吡酮和蒽醌类成分的分离与鉴定

对莽吉柿(Pericarpium Garciniae Mangostanae)85%乙醇提取物进一步分离,得到8个双苯吡酮类化合物和1个蒽酮类化合物,经理化性质和NMR及MS谱学数据鉴定分别为α-倒捻子素-3,6-二乙酸酯（α-mangostin-3,6-diyl diacetate,Ⅰ）、1,5,8-三羟基-3-甲氧基-2,4-双-（3-甲基丁-2-烯）双苯吡酮（8-hydroxycudraxanthone G,Ⅱ）、1,3-二羟基-6,7-二甲氧基-2,8-双-（3-甲基丁-2-烯基）双苯吡酮（Cowaxanthone B,Ⅲ）、1,6-二羟基-3,5-二甲氧基-2-（3-甲基丁-2-烯基）双苯吡酮（Cowaxanthone A,Ⅳ）、1,5-二羟基-4-（3-甲基丁-2-烯基）-6′,6′-二甲基吡喃[2′,3′:3,2]双苯吡酮（trapezifolixanthone,Ⅴ）、1,6-二羟基-6′,6′-二甲基吡喃[2′,3′:7,8]-6″,6″-二甲基吡喃[2″,3″:3,2-]双苯吡酮（brasilixanthone B,Ⅵ）、1,3,5-三羟基-2-（3-甲基丁-2-烯）-4-（1,1-二甲基-2-烯丙基）双苯吡酮（Allanxanthone A,Ⅶ）、1,3,8-三羟基-5-甲氧基-2,4-双-（3-甲基丁-2-烯）双苯吡酮(2,4-di-(3-methylbut-2-enyl)-1,3,8-trihydroxy-5-methoxyxanthone,Ⅷ)、1,4,8-三羟基-6-甲基-3-甲氧基-9,10-蒽酮(1,4,8-trihydroxy-6-methyl-3-methoxy- 9,10-anthraquinone, Ⅸ）。 其中化合物Ⅰ、Ⅴ、Ⅵ、Ⅶ、Ⅸ为首次从藤黄属植物中分离得到,化合物Ⅱ、Ⅲ、Ⅳ、Ⅷ为首次从该植物中分离得到。     

裂解气相色谱-质谱法研究聚醚酰亚胺的热裂解行为

采用裂解气相色谱-质谱技术研究了聚醚酰亚胺(PEI)在550℃、650℃和750℃裂解温度下的热分解行为.随着裂解温度上升,裂解产物明显增加.在750℃时聚合物分子链断裂完全,共鉴别到25种碎片组分.PEI热分解的碎片中叔丁基苯酚、叔丁基甲基苯酚、苯酚、苯胺、氰苯、2-苯基-1H-异吲哚-1,3(2H)-二酮等5种裂解产物最重要,因此可以依据这几种化合物定性鉴别聚醚酰亚胺.依据热分解产物的数量以及结构推断降解机理为:裂解首先从醚键开始,其次是酰胺基团中的C-N键,然后再经过一系列消除反应、成环反应、重排反应等形成多种裂解碎片.     

2种氧杂类大环化合物的光合成

在乙腈溶液中,6,6′-二甲基-4,4′-(三亚甲二氧基)-二-2-吡喃酮与乙二醇二甲基丙烯酸酯类化合物（n=1~3）在二苯酮的光敏化作用下,经由光二重[2+2]环加成反应,同时合成了2种氧杂类的大环化合物,收率为14%和7%、20%和11%及31%和14%。 产物的结构经FTIR、1H NMR和MS表征。 该法具有反应条件温和、操作简单和对环境友好的优点。     

环己酮吗啉烯胺苯甲酰化产物的结构

催化氢化、红外、核磁、质谱等试验进一步证明了Helmers提出的二苯甲酰化烯胺的结构是(2-吗啉-4′基-2-环已烯-1-基)苯基酮烯醇苯甲酸酯(Ⅳ).     

基于质谱的六硝基六氮杂异伍兹烷热分解动力学

采用低能电子轰击质谱研究了六硝基六氮杂异伍兹烷(HNIW)的裂解过程, 建立了质谱中离子强度曲线的非等温动力学处理方法, 根据产物离子的Arrhenius曲线解释了HNIW热分解的机理. 结果表明, HNIW质谱裂解的表观活化能为145.1 kJ·mol-1. 在130-150 ℃范围内, HNIW质谱的离子产物主要是电子轰击产生的, 其活化能在28-41 kJ·mol-1之间; 在213-228 ℃范围内, 离子主要是热分解产生的, 其活化能在143-179 kJ·mol-1之间. HNIW在213-228 ℃的热分解动力学参数存在良好的动力学补偿效应, 补偿效应公式为lnA=0.252Ea-0.645. HNIW 热分解的主要反应为HNIW.438→6NO2+2HCN+HNIW.108, HNIW.438→6NO2+3HCN+HNIW.81, HNIW.438→6NO2+4HCN+HNIW.54.     

烟草中β-胡萝卜素的热裂解产物的研究

为了研究烟草中β-胡萝卜素的高温裂解产物对卷烟抽吸品质的影响,利用热裂解气相色谱/质谱联用仪在不同裂解氛围(空气、氮气中含10%O2及N2)和不同温度(300,600和900 ℃)下对β-胡萝卜素进行裂解,裂解产物用固相微萃取装置进行吸附,然后将吸附到的裂解产物用气相色谱/质谱联用仪(GC/MS)进行分析。结果表明,β-胡萝卜素在不同裂解条件下主要的裂解产物是甲苯、对二甲苯、1,2,3,4-四氢-1,1,6-三甲基萘和2,7-二甲基萘等化合物,另外还生成异佛尔酮、β-环柠檬醛、β-紫罗兰酮、二氢猕猴桃内酯等香味化合物,这些物质随裂解温度和裂解氛围的不同其含量有所差异。     

芳香型螺双内酯二胺的合成

以对硝基甲苯和多聚甲醛为原料,经过两种途径合成了二氨基芳香型螺双内酯--6,6′-二氨基-3,3′-螺双苯酞.发现二(2-甲基-5-硝基苯基)甲烷在酸性体系中经氧化反应可高收率地得到二硝基螺双内酯,还原二硝基螺双内酯时发现,在低极性溶剂中主要生成一种稳定的芳香型羟胺类化合物--6,6′-二羟氨基-3,3′-螺双苯酞,在高极性溶剂中主要生成6,6′-二氨基-3,3′-螺双苯酞.通过¹HNMR,¹³CNMR,IR,MS及元素分析确证了二氨基螺双内酯及其中间产物的结构     

干姜中的二芳基庚烷类化合物及其在四逆汤煎煮过程中的立体选择性反应

采用高效液相色谱多级质谱联用鉴定了干姜水煎剂的18个二芳基庚烷类化合物。发现此类化合物的电喷雾质谱碰撞诱导裂解反应的特征主要表现在吡喃环的次级逆Diels Alder反应裂解或C1和C5OH发生次级麦氏重排裂解,这两种裂解反应对归属芳环的取代非常重要。比较了复方四逆汤配伍对二芳基庚烷类化合物的影响,从色谱保留行为、质谱数据等推测化合物2-(3,4-二羟基-5-甲氧基苯基)-6-(3,4-二羟基苯乙基)-2氢-吡喃-4-醇(Ⅲ-1)的一组差向异构体,2-(3,4-二羟基-5-甲氧基苯基)-6-(4-羟基苯乙基)-2氢-吡喃-4-醇(Ⅲ-2)的一组差向异构体以及2-(3,4-二羟基-5-甲氧基苯基)-6-(4-二羟基-3-甲氧基苯乙基)-2氢-吡喃-4-醇(Ⅲ-3)的2组差向异构体在复方煎煮过程中发生显著的立体选择性反应,由外消旋体变成单一旋光异构体。吡喃环4-位的乙酰化可能是减少这种反应的关键因素。     

N-二氯乙酰基-3,6-二甲基-3-乙基-9-氧代-1,5-二氮杂二环[4.3.0]壬烷的合成及生物活性研究

合成了新型除草剂安全剂N-二氯乙酰基-3,6-二甲基-3-乙基-9-氧代-1,5-二氮杂二环[4.3.0]壬烷.以丁酮为原料,与硝基甲烷作用,制得二硝基化合物,然后将其还原,还原产物与乙酰丙酸成环,再与二氯乙酰氯反应,即得到标题化合物.采用红外光谱、核磁共振谱和元素分析对产物进行了结构表征,并利用土培法对其进行了初步的生物活性测定.结果表明:化合物能够减轻绿磺隆对玉米的伤害.     

二氢吡咯并(口恶)嗪酮类化合物的EI质谱及其解析

总结和归属了(1H)-3,4-二氢吡咯[2,1-c][1,4]噁嗪-1-酮及其6个苯甲酰基衍生物和两个苯乙酰基衍生物在电子轰击电离质谱(EIMS)中的主要裂解方式和特征,指明了主要碎片离子的来源和结构。这8个芳酰基衍生物质谱图中的主要碎片峰均来自α-裂解和脱中性小分子碎片的重排裂解,由其产生的m／z 164、m／z 120和m／z 92离子是该类化合物共同的特征离子;二氢吡咯噁嗪酮苯甲酰基衍生物和苯乙酰基衍生物的基峰都为m／z 164。     

Theoretical studies on vibrational spectra of some halides of group IVB elements

The vibrational spectra of group IVB elements halides MX4 (M=Ti(IV), Zr(IV), Hf(II); X=F, Cl, Br and I), have been investigated by ab initio RHF, MP2 and density functional theory B3LYP method with LanL2DZ basis sets. The optimized geometries, calculated vibrational frequencies and Far-IR intensities of MX4 are evaluated via comparison with experimental data. The vibrational frequencies, calculated by these methods, are compared to each other. The results indicate that B3LYP method is more reliable than RHF and MP2 methods for the frequencies calculations for these compounds. With this method, some vibrational frequencies of M2X6(2+)(M=Ti(IV), Zr(IV) and Hf(II); X=F, Cl, Br and I) are also predicted.     

Theoretical study of valence photoelectron spectra of Re(CO)5X (X=Cl, Br, and I): a spin-orbit DK3 symmetry-adapted cluster/symmetry-adapted cluster-configuration interaction study

The valence photoelectron spectra of Re(CO)(5)X (X=Cl, Br, and I) are studied theoretically using symmetry-adapted cluster (SAC)/SAC-configuration interaction (SAC-CI) theory. The relativistic effects are included by the third-order Douglas-Kroll (DK3) method, and the spin-orbit coupling is also considered. Both electron correlation and relativistic effects are significant in assigning the valence photoelectron spectra of Re(CO)(5)X (X=Cl, Br, and I). DK3-SAC/SAC-CI provides values for the relative peak positions in a reasonable agreement with the observed photoelectron spectra. The sequence of ionization energies for Re(CO)(5)Cl, Re(CO)(5)Br, and Re(CO)(5)I are calculated as e(')[a(1)(Cl)]>e(')[e(Re+Cl)] approximately e(")[e(Re+Cl)]>e(")[b(2)(Re)]>e(')[e(Re-Cl)]>e(")[e(Re-Cl)], e(')[a(1)(Br)]>e(')[e(Re+Br)]>e(")[e(Re+Br)+b(2)(Re)]>e(")[b(2)(Re)+e(Re+Br)]>e(')[e(Re-Br)]>e(")[e(Re-Br)], and e(')[e(Re+I)+a(1)(I)]>e(")[b(2)(Re)+e(Re+I)] approximately e(')[a(1)(I)+e(Re+I)]>e(")[e(Re+I)+b(2)(Re)]>e(')[e(Re-I)]>e(")[e(Re-I)], respectively. These assignments are quite new and different from previous assignments.     

某些有机钨卤化物RC~5H~4(CO)~3WX(R=MeCO, MeO~2C, EtO~2C; X=Cl, Br, I)的合成及结构鉴定

通过酮基或酯基官能团取代的环戊二烯基(三羰基)钨钠 RC~5H~4(CO)~3WN(R=MeCO, MeO~2C, EtO~2C 与I~2、Px~3(X=Cl、Br、I), PhPCl~2, p-MeC~6H~4PCl~2或MeAsI~2 反应, 结果得到8个含相应官能团的有机钨卤化物。用X射线衍射法鉴定了其中 R=MeCO, X=Br的单晶分子结构, 晶体属单斜晶系, 空间群P~21。     

Pressure-induced formation of molecular B2X4(μ-X)2 (X = Cl, Br, I) species

Boron(III) halides (BX(3), where X = F, Cl, Br, I) at ambient pressure conditions exist as strictly monomeric, trigonal-planar molecules. Using correlated ab initio calculations, the three heavier halides (X = Cl, Br, I) are shown to possess B(2)X(4)(μ-X)(2) local minima, isostructural with the diborane molecule. The calculated dissociation barrier of the B(2)I(4)(μ-I)(2) species [≈14 kJ/mol with CCSD(T)/cc-pVTZ] may be high enough to allow cryogenic isolation. The remaining dimer structures are more labile, with dissociation barriers of less than 6 kJ/mol. All three dimer species may be stabilized by application of external pressure. Periodic density functional theory calculations predict a new dimer-based P1 solid, which becomes more stable than the P6(3)/m monomer-derived solids at 5 (X = I) to 15 (X = Cl) GPa. Metadynamics simulations suggest that B(2)X(4)(μ-X)(2)-based solids are the kinetically preferred product of pressurization of the P6(3)/m solid.     

Solid-state 207Pb NMR studies of mixed lead halides, PbFX (X=Cl, Br, or I)

Solid-state 207Pb NMR studies have been conducted on mixed lead(II) halides of the type PbFX, where X=Cl, Br, or I. NMR data for the mixed halides are compared to the solid-state NMR data for the divalent, binary lead halides, PbX2 (X=F, Cl, Br, I). The NMR data are evaluated in the context of the structures of the compounds and the effects of the mixed halides on the electronic structure of the divalent lead. Data sets for the mixed halides are discussed and compared to those for the regular lead(II) halides.     

Synthesis of carbaalane halogen derivatives

The carbaalane halogen derivatives [(AlX)(6)(AlNMe(3))(2)(CCH(2)CH(2)SiMe(3))(6)] (X = F (9), Cl (7), Br (10), I (11)) were prepared in toluene from [(AlH)(6)(AlNMe(3))(2)(CCH(2)CH(2)SiMe(3))(6)] (6) and BF(3).OEt(2), BX(3) (X = Br, I), Me(3)SnF, and Me(3)SiX (X = Cl, Br, I), respectively. A partially halogenated product [(AlH)(2)(AlX)(4)(AlNMe(3))(2)(CCH(2)CH(2)SiMe(3))(6)] (12) (X = Cl (approximately 40%), Br (approximately 60%)) was obtained from 5 and impure BBr(3). [(AlH)(6)(AlNMe(3))(2)(CCH(2)Ph)(6)] (5) was converted to [(AlX)(6)(AlNMe(3))(2)(CCH(2)Ph)(6)] (X = F (13), Cl (14), Br (15), I (16)) using BF(3).OEt(2) and Me(3)SiX (X = Cl, Br, I), respectively. The X-ray single-crystal structures of 11.C(6)H(6), 12.3C(7)H(8), 13.6C(7)H(8), and 15.4C(7)H(8) were determined. Compounds 7 and 9-11 are soluble in benzene/toluene and could be well characterized by NMR spectroscopy and MS (EI) spectrometry. The results demonstrate the facile substitution of the hydridic hydrogen atoms in 5 and 6 by the halides with different reagents.     

Hydrolyse und Halogenidaustausch von Pentahalogenomonocarbonylosmaten(III)

Hydrolysis and Halide Exchange of Pentahalogenomonocarbonyl Osmates(III) The aquo complexes [OsX₄(CO)(H₂O)]^?, [OsX₃(CO)(H₂O)] and [OsX₂(CO)(H₂O)₃]⁺, X ? Cl, Br, I, produced by the stepwise hydrolysis of [OsX₅(CO)]^2?, are isolated as pure solutions by ionophoresis and characterized by their absorption spectra. Due to stability of the monaquo complexes and the different trans-effect of the halides it is possible to prepare the mixed complexes [OsX_4–nY_n(CO)(H₂O)]^?, X ≠ Y = Cl, Br, I, n = 1–3, and for n = 2 the pure stereoisomers are formed. A systematic shift is found in charge-transfer bands to the shorter wavelengths when the halides are replaced by H₂O, I by Br or Cl and Br by Cl.     

Ring-opening reactions induced by gold(I) of five- and four-coordinate palladium(II) and platinum(II) complexes containing tripodal or linear polyphosphines

The tripodal ligands NP(3)(tris[2-(diphenylphosphino)ethyl]amine) and PP(3)(tris[2-(diphenylphosphino)ethyl]phosphine), form five-coordinate [Pd(NP(3))X]X [X = Cl (1), Br (2)], [M(PP(3))X]X [M = Pd: X = Cl (4), Br (5), I (6); M = Pt, X = Cl (7), Br (8), I (9)] and four-coordinate[Pd(NP(3))I]I (3) complexes containing three fused rings around the metal. The interaction between Au(tdg)X (tdg = thiodiglycol; X = Cl, Br) or AuI and the respective ionic halo complexes 1-9 in a 1:1 stoichiometric ratio occurs via a ring-opening reaction with formation of the heterobimetallic systems PdAu(NP(3))X(3)[X = Cl (11), Br (12), I (13)], [MAu(PP(3))X(2)]X [M = Pd: X = Cl (14), Br (15), I (16); M = Pt: X = Cl (17), Br (18), I (19)]. The cations of complexes 17 and 18 were shown, by X-ray diffraction, to contain a distorted square-planar Pt(II) arrangement (Pt(P(2)P)X) where PP(3) is acting as tridentate chelating ligand and an almost linear PAuX moiety bearing the dangling phosphorus formed in the ring-opening process. PPh(3) coordinates to Au(I) and not to M(II) when added in excess to 14 and 17. Complexes 14-17 and [Pt(P(4))](BPh(4))(2) (10) (P4=linear tetraphosphine) also react with A(I), via chelate ring-openings to give MAu(2)(PP(3))X(4) [M = Pd: X = Cl (20), Br (21), I (22); M = Pt: X = Cl (23)] and [Pt(2)Au(2)(mu-Cl)(2)(mu-P(4))(2)](BPh(4))(4) (24), respectively.     

Helical sexithiophenes: an experimental and theoretical study implicating the alternating 2,2':3,3' regioisomer as a reliable helical motif

Perchlorinated sexithiophene regioisomer, 2,2' ' '-diX-5,5',5' ',5' ',5' ' ',5' ' '-hexachloro-[3,3';2',2' ';3' ',3' ';2' ',2' ' ';3' ' ',3' ' ']sexithiophene (compound 1), demonstrates a reliable helical conformation in the solid state, regardless of a broad range of substituents, X. The synthesis and composition of compound 1a (X = H) synthetically accommodates substituent diversity at the 2- and 2' ' '-sites. X-ray crystal structures (X = H, Cl, Br) and theoretical geometry optimizations (X = H, Cl, Br, I, Me, Et, t-Bu, and Ph) both confirm that the helical state, a conformation likely dictated by internal torsional strain, is predominant and unaffected by substituent X. It is predicted (ACID/B3LYP/6-31G(d) calculations and UV-visible spectra) that the helical structure exists as a fully conjugated system.     

New ternary and quaternary barium nitride halides; synthesis and crystal chemistry

New ternary and quaternary nitride halides, Ba(2)N(X,X') (X = F, Cl, Br; X' = Br, I), have been synthesized from the high temperature reactions of barium subnitride with the respective barium halides under an inert atmosphere. The former include the first fully characterized barium nitride halides for X other than F, and the latter are the first examples of barium nitride mixed halides. The variation in structure with composition has been investigated by powder X-ray and powder neutron diffraction techniques. The heavier ternary and quaternary nitride halides (X, X' = Cl, Br, I) crystallize in the hexagonal space group R3m, with the anti-α-NaFeO(2) structure. Ba(2)NF forms with both an anti-α-NaFeO(2) structure, in which N(3-) and F(-) are ordered and an anion-disordered simple rock salt structure. The hexagonal polymorph of Ba(2)NF is the only example to date of a nitride fluoride adopting this layered structure. Both the ternary and the quaternary compounds display very weak, temperature independent paramagnetism.