苯并噻唑-2-甲醛合成方法的改进

以邻氨基苯硫酚为原料,先与羟基乙酸反应合成2-羟甲基苯并噻唑,然后通过氧化反应生成苯并噻唑-2-甲醛。对比了几种氧化剂的效果,发现二氧化锰氧化的效果最好。优化的反应条件为,2-羟甲基苯并噻唑与二氧化锰的摩尔比为1∶8,回流反应8h,产率可达90.2%。该方法适合苯并噻唑-2-甲醛及其衍生物的大规模生产。     

硒催化羰基化合成苯并噻唑-2-氨基甲酸酯

以非金属Se为催化剂,以CO替代剧毒光气及其复杂衍生物作羰基化试剂,以O2为氧化剂,经2-氨基苯并噻唑与醇发生"一锅法"的硒催化氧化羰基化反应,开辟了一条经济、绿色、简便、高效的合成苯并噻唑-2-氨基甲酸酯类化合物的新途径.研究了反应温度、压力、醇的用量及碱的种类等因素对生成苯并噻唑-2-氨基甲酸酯的影响,获得了实施该...     

6-取代苯并噻唑-2-氨基硫代磷酸二烷基酯的合成

用6-位取代的2-氨基苯并噻唑与三氯硫磷反应,合成了3个苯并噻唑-2-氨基硫代磷酰二氯,并由此合成了9个苯并噻唑-2-氨基硫代磷酸二烷基酯.讨论了苯并噻唑环上取代基对反应的影响和产物中硫代磷酸酯的烷基的空间效应对反应的影响.所合成的部分化合物对人喉鳞状细胞癌(Hep-2)具有一定的抑制能力.     

新型2-苯并噻唑磺酰脲氨基酸及其甲酯衍生物的合成与抗肿瘤活性

以2-巯基苯并噻唑为原料,经弱氧化和氨化制得2-苯并噻唑次磺酰胺（2）; 2经高锰酸钾氧化制得2-苯并噻唑磺酰胺（3）; 3与氯甲酸乙酯反应制得2-苯并噻唑磺酰胺甲酸乙酯（4）; 4与L-氨基酸甲酯反应制得一系列2-苯并噻唑磺酰脲氨基酸甲酯（6a~6j）; 6经水解合成了10个新型的2-苯并噻唑磺酰脲氨基酸（7a~7j）,其结构经¹H NMR, IR和ESI-MS表征。并研究了6和7对Cdc25B的抑制活性。结果表明:在用药浓度为20 μg·mL^-1时,6c, 6j, 7d, 7h和7j对Cdc25B抑制活性较好,抑制率分别为78.1%, 71.2%, 65.6%, 57.2%和65.9%。     

无溶剂条件下离子液体[Hnmp]HSO4催化一锅法合成2 -氨基苯并噻唑-芳甲基-2-萘酚

以离子液体[Hnmp]HSO₄为催化剂, 在无溶剂条件下催化芳香醛、2-氨基苯并噻唑和2-萘酚合成一系列的2 -氨基苯并噻唑-芳甲基-2-萘酚. 该方法条件温和, 反应时间短, 产率高和对环境友好. 此外催化剂可以方便地回收, 且循环使用四次其催化活性并没有显著降低. 目标产物经过了¹H NMR, IR, MS和元素分析确证.     

2-芳基乙烯基苯并噻唑的催化合成及其紫外光谱的取代基效应

甲基苯并噻唑;固相催化剂;缩合反应;2-芳基乙烯基苯并噻唑的催化合成及其紫外光谱的取代基效应     

N-取代苯基-N′-[6-(2-甲基苯并噻唑)基]脲类化合物的合成

以 2 -甲基苯并噻唑和取代苯胺为原料 ,合成了 7个 N-取代苯基 -N′-[6-( 2 -甲基苯并噻唑 )基 ]脲类新化合物 ,产率分别为 82 .0 % ,88.5% ,87.0 % ,90 .5% ,91 .0 % ,83.5%和 85.0 %。其结构经元素分析、IR和1 H NMR确定。     

N-取代苯基N'-(6-苯并噻唑基)脲类化合物的合成

为了寻找具有植物细胞激动素活性的新化合物,以苯并噻唑和取代苯胺为原料,将取代苯脲基引入到苯并噻唑的6-位上,合成了7个N-取代苯基N'-(6-苯并噻唑基)脲类化合物,它们的结构经元素分析、IR和1HNMR确定,7个化合物的合成收率分别为74%,76%,85%,82%,70%,73%和72%.     

1-苯基-3-芳基-4-甲酰基吡唑衍生物的合成及其荧光性能

以苯肼和4-取代苯乙酮(1a～1d)为原料, 经过缩合, 再与Vilsmeier-Haak试剂反应合环, 制得1-苯基-3-芳基-4-甲酰基吡唑(3a～3d), 将其与2-肼基-4/6-取代苯并噻唑(4a～4f)反应, 合成一系列新化合物1-苯基-3-芳基-吡唑-4-醛 [N-(4/6-取代苯并噻唑-2-基)]腙5～8. 所有新化合物的结构均经IR, ¹H NMR, MS谱和元素分析证实. 对化合物5～8的荧光进行了测定, 结果显示这些化合物具有荧光特性, 并探讨了化合物的结构对荧光性能的影响.     

两个基于苯并噻唑-2-硫酮的银(Ⅰ)配合物的合成、晶体结构和光谱性质

合成了2个含有杂环硫酮的银(Ⅰ)配合物,[AgCl(PPh₃)₂(BTZT)]₂ (1),[Ag(PPh₃)₂(BTZT)₂](NO₃)CH₃OH (2)(PPh₃=三苯基膦; BTZT=苯并噻唑-2-硫酮),并通过红外光谱、X射线单晶衍射、荧光光谱和核磁共振氢谱进行表征和分析。杂环硫酮存在化学活性基团-N(H)-C(=S)-,在平衡中与其硫醇形式可以相互转化。2个配合物是在含有2-巯基苯并噻唑(MBT)的甲醇与二氯甲烷混合溶液中,AgCl或AgNO₃与三苯基膦反应得到的。配合物1的每个不对称单元中包含2个相同的分子结构,但是它们具有不同的键长和键角。配合物2是一个简单的单核杂配配合物,它的主体结构通过氢键作用连接游离的CH₃OH和NO₃^-离子。配合物1和2发射峰的红移源于配体中的π-π^*跃迁。     

Use of a chiral surfactant for enantioselective reduction of a ketone

The influence of a chiral surfactant and a polymer-supported chiral additive on reduction of ketones using sodium borohydride will be described. Initial preparations involved methylation of (S)-leucinol to give (2S)-N , N-dimethyl-2-amino-4-methyl-1-pentanol (1) (67%). The chiral surfactant (2) was synthesized by reacting (1) with bromohexadecane (71%). The functionalized styrene for the polymer-supported chiral additive (5) was synthesized by reacting (1) with 4-vinylbenzyl chloride. Polymerization was carried out with 10% of the functionalized monomer (4), 5% cross-linking agent divinylbenzene, and 85% styrene with AIBN as the initiator. The activity of the chiral surfactant and polymeric additive were examined by using them as additives in a standard reduction of 2-pentanone with sodium borohydride to yield (R)- and (S)-2-pentanol (3) (20%). The resulting alcohol was analyzed by polarimetry (ee 9.5%) and also esterified with (2S)-methylbutyric acid prior to characterization by NMR. 13C NMR indicated an enantiomeric excess of 5.2% when the chiral surfactant was used, and 7% when the polymeric additive was used.     

煤酸浆态床异构化制对苯二甲酸

在分别使用有机高沸点分散剂联苯和联三苯的条件下,以苯甲酸锌为催化剂,进行了煤氧化产物煤酸(水溶酸WSA)钾浆态床异构化制对苯二甲酸(TPA)的研究。主要考察了反应温度、催化剂用量、分散剂用量、二氧化碳初压和反应时间对TPA产率的影响。结果表明,在催化剂存在下煤酸可以转化成TPA。单独煤酸钾异构化时,以联苯为分散剂时较佳反应条件为温度420℃、压力3MPa、催化剂苯甲酸锌用量3%、分散剂用量60%、反应时间1h、TPA收率24.1%。以联三苯为分散剂时较佳反应条件为温度380℃、压力1MPa、催化剂苯甲酸锌用量3%、分散剂用量60%、TPA收率25.2%。煤酸钾与苯甲酸(BA)钾混合异构化时,以联苯为分散剂TPA产率可达60%,以联三苯为分散剂TPA产率可达62%。采用气相色谱对反应产物进行了定性和定量分析。     

S(RN)1 Reactions of 7-Iodobicyclo[4.1.0]heptane, 1-Iodoadamantane, and Neopentyl Iodide with Carbanions Induced by FeBr(2) in DMSO

There was no reaction of 7-iodobicyclo[4.1.0]heptane (7-iodonorcarane, 1) (exo-endo ratio of ca. 1) with acetophenone enolate ions 2 in DMSO at 25 degrees C; however, with the addition of SmI(2) or FeBr(2) and under the same experimental conditions, the substitution product 3 was obtained in 9% and 72% yields, respectively, with an exo-endo ratio of ca. 16 similar to the product ratio from photostimulated reactions. Thus, it seems that 7-norcaranyl radicals are intermediates of these reactions. With FeBr(2) at 60 degrees C the yield of 3 was as high as 90%. Reactions of 1 with the enolate ion of 2-naphthyl methyl ketone 4 induced by FeBr(2) gave substitution product 5 in 60% yield (96% of it the exo isomer). In competition experiments, 4 was 1.7 times more reactive than 2, and the anion of nitromethane (7) was 6.5 times more reactive than 2 toward 7-norcaranyl radicals. The reactions of 1-iodoadamantane (9) and neopentyl iodide (11) with carbanion 2 induced by FeBr(2) gave the substitution products in 85% and 92% yields, respectively. These observations indicate that all these reactions induced by FeBr(2) occur by the S(RN)1 mechanism.     

三种O－异戊烯基苯丙素类天然产物的首次合成

以香草醛为起始原料，经O－异戊烯基化、Witting反应、水解、还原、氧化等 反应步骤，首次合成了三种苯丙素天然产物boropinalA（1），boropinalC（2） boropinicAcid（3）,有化合物结构均由核磁共振氢谱，质谱及红外光谱确证，用 X射线衍射法测定了3的晶体及分子结构。     

光促进下N,N-二甲基甲酰胺作为一氧化碳源的烯烃氢酯化反应

 研究了光照下以N,N-二甲基甲酰胺(DMF)为一氧化碳源的烯烃氢酯化反应. 结果表明,在常温常压和光照射条件下DMF可以分解得到CO,新生成的CO在光促进下可以直接与CH3OH-DMF溶液中的底物1-辛烯在温和条件和非贵金属钴化合物(Co(OAc)2,CoCl2,Co(en)3Cl2和大环钴[Co(14)4,11-二烯-N4]I2)催化下进行氢酯化反应,反应中DMF既是溶剂,又是原料. H13CON(CH3)2同位素示踪实验证实了这一结果. 在反应体系中通入二氧化碳可以大大提高反应的转化率、产率及选择性. 13CO2同位素示踪实验表明,CO2并未参与产物的形成,其作用是中和DMF分解产生的HN(CH3)2,从而有利于DMF的光促分解.     

High performance thermoelectrics from earth-abundant materials: enhanced figure of merit in PbS by second phase nanostructures

Lead sulfide, a compound consisting of elements with high natural abundance, can be converted into an excellent thermoelectric material. We report extensive doping studies, which show that the power factor maximum for pure n-type PbS can be raised substantially to ~12 μW cm(-1) K(-2) at >723 K using 1.0 mol % PbCl(2) as the electron donor dopant. We also report that the lattice thermal conductivity of PbS can be greatly reduced by adding selected metal sulfide phases. The thermal conductivity at 723 K can be reduced by ~50%, 52%, 30%, and 42% through introduction of up to 5.0 mol % Bi(2)S(3), Sb(2)S(3), SrS, and CaS, respectively. These phases form as nanoscale precipitates in the PbS matrix, as confirmed by transmission electron microscopy (TEM), and the experimental results show that they cause huge phonon scattering. As a consequence of this nanostructuring, ZT values as high as 0.8 and 0.78 at 723 K can be obtained for nominal bulk PbS material. When processed with spark plasma sintering, PbS samples with 1.0 mol % Bi(2)S(3) dispersion phase and doped with 1.0 mol % PbCl(2) show even lower levels of lattice thermal conductivity and further enhanced ZT values of 1.1 at 923 K. The promising thermoelectric properties promote PbS as a robust alternative to PbTe and other thermoelectric materials.     

On the application of the Dumas technique for the determination of nitrogen in refractory nitrides

The classical Dumas apparatus has been modified. The generally recommended oxidants CuO and V(2)O(5), were found to give relatively high blank values and were therefore replaced by Cu(2)O. The preparation of the Cu(2)O is described. It is an exceptionally suitable oxidant for the Dumas analysis of the Group Va nitrides as well as manganese nitrides and molybdenum nitrides because it does not release oxygen into the gas phase. The reaction of the Group IVa nitrides as well as of CrN with CuO and Cu(2)O is, however, not completely quantitative at 1000-1150 degrees in reasonable reaction times. The results of the Dumas analysis of a Group IVa nitride should be corrected by measuring the nitrogen content of the residue (e.g., by hot extraction). The relative standard deviations do not exceed 0.38%. The nitrogen contents (% w/w) of the residues range from <0.001% for Mo(2)N + MoN to 0.54% for Cr(2)N + CrN. BN, Si(3)N(4) and AlN could not be decomposed with copper oxides under the conditions used. AlN could be analysed by adding V(2)O(5), but the rsd was 0.55% and the nitrogen content in the residue was 0.52% w/w. Neither BN nor Si(3)N(4) could be analysed by addition of V(2)O(5).     

The molecular structure of selenium dibromide as determined by combined gas-phase electron diffraction-mass spectrometric experiments and quantum chemical calculations

The vapour over solid SeBr(4) at 10 degrees C was investigated with a combined gas-phase electron diffraction/mass spectrometric (GED/MS) method. The composition of the vapour derived from the mass spectra (43% SeBr(2), 56.7% Br(2) and 0.3% Se(2)Br(2)) was in agreement with the composition obtained from the analysis of the simultaneously recorded GED intensities (41(3)% SeBr(2), 59(3)% Br(2)). The GED study results in the following geometric parameters (r(g), angle(g) values with total uncertainties): Se-Br = 2.306(5) A and Br-Se-Br = 101.6(6) degrees . Most quantum chemical approximations (B3LYP, MP2, CCSD and CCSD(T) with relativistic effective core potentials and cc-pVTZ as well as aug-cc-pVTZ basis sets for the outer shells) overestimate the Se-Br bond length by 0.01 to 0.03 A. All methods reproduce the bond angle correctly, except for the B3LYP method. Gas phase vibrational frequencies estimated from experimental vibrational amplitudes agree well with those measured by Raman spectroscopy in acetonitrile solutions. All computational methods overestimate vibrational frequencies, especially that for the symmetric stretch vibration, by about or 8 to 13%.     

钴联吡啶配合物在硅电极表面高效光电催化二氧化碳还原反应（英文）

光驱动二氧化碳还原实现可再生能源转化近年来引起普遍关注.利用小分子金属配合物电催化剂和吸光半导体材料构建的光电催化体系兼具电催化剂的高选择性和光电极的高光电转化效率等优点,在能源催化领域的应用日益广泛.已有将贵金属配合物催化剂用于光电催化二氧化碳还原的研究报道,但催化剂成本较高且制备方法不简便,在规模化实际应用中受到局限.基于早期的研究报道,我们发现非贵金属多联吡啶铁钴镍配合物在乙腈电解质中能高选择性电催化还原二氧化碳.结合半导体材料的特异性电荷分离性能从而将光能高效转化为电能驱动催化反应进行,我们选择廉价且易于制备的多联吡啶钴配合物催化剂,利用半导体硅晶片光电极,实现了均相体系二氧化碳的高效光电催化还原.我们采用电化学循环伏安法和恒电位电解法分别研究了催化剂在干燥和加水电解质环境中的催化还原行为,并且进一步研究了微量质子源的加入对半导体界面催化过程的影响,从而提出一种能改善半导体光电催化体系选择性的新方法.首先我们构建了电化学三电极体系,研究了在暗环境下三联吡啶钴和二联吡啶钴这两种配合物催化还原二氧化碳的电流密度和电解产物分布情况.由循环伏安曲线发现,这两种配合物都有两组催化还原峰,第二个基于吡啶配体还原的峰具有明显的催化特性.少量水的加入能进一步增加催化电流强度,而三联吡啶钴配合物的催化增强效果更加显著.在变扫速条件下将电流密度对扫速平方根进行归一化处理,发现无论在干燥环境还是少量加水环境下,两种催化剂的归一化电流密度均随扫速降低而明显增强,证明了催化剂具有电催化特性.推测水的催化增强作用可能与质子化电催化过程活性中间体有关.恒电位电解结果说明电催化产物以一氧化碳为主.基于上述研究,我们构建了光电化学三电极体系,以单晶硅片为工作电极,研究了在光照环境下这两种配合物催化还原二氧化碳的电流密度和电解产物分布情况.研究发现,催化剂对二氧化碳仍具有催化活性,光电压为400 m V.不同于硅线电极加水导致产氢,改用少量甲醇做质子源后,光电流强度进一步增强,竞争性产氢受到了抑制,从而使一氧化碳的法拉第效率得到显著提高,分别优化为94%和83%,并且光电流在14h内保持稳定.推测甲醇质子源的催化增强作用可能是与改变光电极液接界面传质动力学过程有关.     

Catalytic asymmetric cyclocarbonylation of o-isopropenylphenols: enantioselective synthesis of six-membered ring lactones

Cyclocarbonylation of o-isopropenylphenols with CO (500 psi) and H(2) (100 psi), using Pd(OAc)(2) and (+)-DIOP as the chiral catalyst, in CH(2)Cl(2) affords 3,4-dihydro-4-methylcoumarins in 60-85% yield and in up to 90% enantiomeric excess. The stereoselectivity is influenced by the structure of the chiral phosphine ligands and substrates, as well as by the reaction conditions.