一类2(1H)-喹喔啉化合物的裂解机理

用电子轰击质谱（EI-MS）研究了一类喹喔啉化合物；1-烷基-3-甲基-2（1H）-喹喔啉-2-酮（1-alkyl-3-methyl-2(1H)-quinoxalin-2-one，简称AMQ，其中alky1=H,CH3，C2H5，n-C3H7，n-C5H11；结果表明随着烷基链的增长，样品熔点通常会有所降低，结合在电子轰击下所产生的裂解碎片离子，并根据其结构特征为乙基化样品为代表，推导了该类化合物在电子轰击作用下可能发生的裂解机理。     

1-苯基-3-甲基-6-N,N-二正丁基胺-2(1H)-喹喔啉-2-酮的全合成

报道了2(1H)-喹喔啉类衍生物——1-苯基-3-甲基-6-N,N-二正丁基胺-2(1H)-喹喔啉-2-酮的全合成.该化合物及其中间体1-苯基-3-甲基-6-胺基-2(1H)-喹喔啉-2-酮和1-苯基-3-甲基-6-硝基-2(1H)-喹喔啉-2-酮均为新化合物,文中给出了它们的重要的分析数据,简要讨论了溶剂在关环反应以及N-烷基化反应中的重要影响,偶然发现以水作溶剂时关环主产物为1-苯基-3-甲基-5-硝基-苯并咪唑.这类化合物可应用于药物,如用作N-甲基-D-天冬氨酸(NMDA)受体及α-氨基羟甲基异噁唑丙酸(AMMPA)受体拮抗剂、杀菌剂等;还可用作植物生长抑制剂、荧光探针以及作为新型功能染料中间体等诸多领域.     

一类2(1H)-喹喔啉衍生物的电子轰击质谱分析

以邻苯二胺为原料合成表征了一类喹喔啉衍生物；1-烷基-3-甲基-2（1H）-喹喔啉-2-酮（1-alkyl-3-methly-2(1H)-quinoxalin-2-one，简称AMQ，其中alky=H、CH3、Et、n-C3H5、n-C5H11、n-C16H33)。用电子轰击电离质谱（EI-MS）和核磁共振谱图（^1H-NMR)鉴定了AMQ，研究了不同取代基对这类化合物EI-MS谱图的影响，分析得到一些裂解规律。结果表明：所有样品谱图中均有芳香化合物的特征CnHn^ 系列峰m/z78，65，52，39和（或）m/z77、76、64、63、51、50、38、37。对于末取代的样品及低级烷烃取代的样品，谱图中的基峰为分子离子峰，对于取代基中碳数大于等于3的样品。谱图中的基峰不是分子离子峰，分子离子峰强度随着碳数的增加而降低。这些样品一般容易发生骨架重排，丢失一分子CO，生成1-烷基-2-甲基苯并哒唑正离子。此外，还讨论了谱图中其它的一些碎片离子峰。这对于研究和指导喹喔啉衍生物 的合成，探讨它们在药效及结构特征与生理活性的关系等方面具有重要的应用价值和理论意义。     

2-溴甲基-3-(二溴甲基)喹喔啉的合成研究

以2，3－二（溴甲基）喹喔啉为原料，以N－溴琥珀酰亚胺为溴化试剂合成了2－溴甲基－3－（二溴甲基）喹喔啉（1），1是Diels-Alder环加成反应中形成含杂原子环的C60衍生物的一种重要中间体。通过IR，^1H NMR,^13C NMR,DEPT谱和MS对其进行了结构表征。     

过硫酸铵促进喹喔啉-2(1H)-酮三氟甲基化反应

报道了温和条件下,过硫酸铵促进喹喔啉-2(1H)-酮与CF3SO2Na三氟甲基化制备3-三氟甲基喹喔啉-2(1H)-酮类的反应,开发了一种绿色、高效制备3-三氟甲基喹喔啉-2(1H)-酮衍生物的方法.该方法对不同取代的喹喔啉-2(1H)-酮衍生物具有较好的适用性,均以较高的产率得到相应的目标产物.与已有方法相比,本方法具有底物适用范围广、产率高、实验操作简便等优点,为3-三氟甲基喹喔啉-2(1H)-酮的制备提供了有效的路径.     

新型2-甲基-6-(N,N-二烷基氨基)喹喔啉的合成

以4-硝基邻苯二胺为原料，经缩合、硝基还原和N-烷基化反应合成了一系列具有新颖结构的2-甲基-6-(N,N-二烷基氨基)喹喔啉，其结构经¹H NMR, ¹³C NMR, HR-MS（ESI）和XRD表征。     

2-甲基-6-二乙胺基乙氧基-3(2H)-哒嗪酮的合成及其电子性质

分别利用两种方法合成2－甲基－6－二乙胺基乙氧基－3（2H）－哒嗪酮，用^1H NMR,IR,UV和MS进行结构表征，利用ab initio HF和密度泛函理论（DFT）B3LYP方法，对反应物、中间物、产物及其同分异构体进行几何结构的优化和总能量计算，系统分析前线分子轨道特征和能级分布规律，结果表明，2－甲基－6－二乙胺基乙氧基－3（2H）－哒嗪酮比其同分异构体哒嗪氮烷基化合物的能量低，前比后稳定，与实验事实相符合。     

可见光催化喹喔啉-2(1H)-酮与醇C(sp~2)-H/O-H交叉脱氢偶联反应（英文）

杂环化合物和醇的C(sp~2)-H/O-H交叉脱氢偶联反应为制备杂环醚类化合物提供了一种原子和步骤经济性的方法.然而,已经报道的交叉脱氢偶联反应大部分需要使用过渡金属催化剂和/或者强氧化剂,不仅产生环境问题还增加分离成本.同时,这些合成方法还存在杂环化合物和醇的C(sp~2)-H/C(sp~3)-H交叉脱氢偶联反应的竞争反应,降低了反应的选择性和收率.喹喔啉-2(1H)-酮是生物活性物质和人工药物的核心骨架结构之一,合成多样性官能化的喹喔啉-2(1H)-酮备受关注.近期多种C-3官能化喹喔啉-2(1H)-酮的合成方法被报道,但是目前没有一例通过无金属无强氧化剂条件下的喹喔啉-2(1H)-酮与醇C(sp~2)-H/O-H交叉脱氢偶联反应合成3-烷氧基喹喔啉-2(1H)-酮的相关工作报道.值得一提的是,利用氧气作为氧化剂的可见光催化反应符合绿色化学的要求,在最近几年中发展迅速.本文报道了一种通过可见光催化的喹喔啉-2(1H)-酮与醇的C(sp~2)-H/O-H交叉脱氢偶联反应合成3-烷氧基喹喔啉-2(1H)-酮化合物的绿色制备方法.首先通过对光催化剂、溶剂等参数的筛选,确定了最佳反应条件为喹喔啉-2(1H)-酮化合物0.3 mmol,醇0.9 mmol,乙腈1.5 m L, Acr~+-Mes Cl O_4~-2mol%,空气作为氧化剂, 3 W蓝光作为光源.在最佳条件下,含有供电子、吸电子取代基的喹喔啉-2(1H)-酮化合物和含有各种取代基的烷基醇都能很好地进行反应,得到36种目标化合物,产率70%～94%.另外,成功完成了克级放大实验和一锅法串联反应.机理研究证明,该反应是喹喔啉-2(1H)-酮化合物在光催化氧化作用下生成自由基正离子,醇作为亲核试剂选择性进攻自由基正离子的C3位,最后得到目标产物.     

可见光催化喹喔啉-2(1H)-酮与醇C(sp2)-H/O-H交叉脱氢偶联反应(英文)

杂环化合物和醇的C(sp²)-H/O-H交叉脱氢偶联反应为制备杂环醚类化合物提供了一种原子和步骤经济性的方法.然而,已经报道的交叉脱氢偶联反应大部分需要使用过渡金属催化剂和/或者强氧化剂,不仅产生环境问题还增加分离成本.同时,这些合成方法还存在杂环化合物和醇的C(sp²)-H/C(sp³)-H交叉脱氢偶联反应的竞争反应,降低了反应的选择性和收率.喹喔啉-2(1H)-酮是生物活性物质和人工药物的核心骨架结构之一,合成多样性官能化的喹喔啉-2(1H)-酮备受关注.近期多种C-3官能化喹喔啉-2(1H)-酮的合成方法被报道,但是目前没有一例通过无金属无强氧化剂条件下的喹喔啉-2(1H)-酮与醇C(sp²)-H/O-H交叉脱氢偶联反应合成3-烷氧基喹喔啉-2(1H)-酮的相关工作报道.值得一提的是,利用氧气作为氧化剂的可见光催化反应符合绿色化学的要求,在最近几年中发展迅速.本文报道了一种通过可见光催化的喹喔啉-2(1H)-酮与醇的C(sp²)-H/O-H交叉脱氢偶联反应合成3-烷氧基喹...     

光/电化学合成在喹喔啉-2(1H)-酮C—H键官能化中的应用

喹喔啉-2(1H)-酮是一类重要的含氮杂环化合物,具有很强的生物活性与化学特性,在合成化学、功能材料及药物工业等方面具有重要应用.近年来,通过C—H官能化构建3-官能化的喹喔啉-2(1H)-酮引起了很多学者的关注,并取得了重要进展.其中,基于绿色化学导向的光催化及电化学合成正成为喹喔啉-2(1H)-酮的C—H官能化的强有力工具.鉴于光电化学在合成化学中的巨大影响,总结了可见光催化与电化学合成实现喹喔啉-2(1H)-酮3位C—H官能化的研究现状,希望能促进绿色合成策略在含氮杂环官能化中的进一步发展.     

4-Alkoxycarbonyl, 4-alkylthiocarbonyl and 5-alkoxycarbonyloxy derivatives of 1-substituted-3-methylpyrazol-5-ones

The reaction of 1-substituted-3-methylpyrazol-5-ones 1 with alkyl chloroformates and calcium hydroxide in dioxane have been studied. With 1-phenyl-3-methylpyrazol-5-one, the isolated product was alkyl 3-methyl-5-oxo-1-phenylpyrazole-4-carboxylate 2 but with 1-alkyl-3-methylpyrazol-5-one formation of 1-alkyl-5-alkoxycarbonyloxy-3-methylpyrazole 3 was observed. Replacement of alkyl chloroformate by bis(alkoxythiocarbonyl) sulfide results in the formation of 4-alkoxythiocarbonyl derivatives 4 in low yield with both 1-substituted-3-methylpyrazol-5-ones.     

Quenched gas-phase reactions of tetraborane(10), B4H10, with substituted alkynes: new nido-dicarbapentaboranes and arachno-monocarbapentaboranes

New alkyl derivatives of the nido-dicarbapentaborane, 1,2-C(2)B(3)H(7), and arachno-carbapentaborane, 1-CB(4)H(10), have been identified as the main volatile carbaborane products in quenched gas-phase reactions of tetraborane(10), B(4)H(10), with alkyl-substituted ethynes RC[triple bond]CR' (R = Me, Et, (n)Pr or (t)Bu, R' = H; R = Me or Et, R' = Me). The gaseous mixtures were heated at 70 degrees C, and monitored by gas-phase mass spectrometry. Each reaction was quenched when the ethyne was used up. The quenched gas-phase reaction of B(4)H(10) and Me(3)SiC[triple bond]CH gave a single volatile carbaborane product, 1-Me(3)Si-1,2-C(2)B(3)H(6).     

A new approach to the synthesis of strained cyclic systems: II. Mass spectrometric study of 2-dialkylamino-3-phenylthiophenes and their structural isomers, iminothietanes and iminocyclobutenes

Triads of isomeric N-alkyl-N-methyl-3-phenylthiophen-2-amines, N-methyl-3-alkyl-4-methylidene-3-phenylthietan-2-imines, and N-methyl-4-alkylsulfanyl-2-phenylcyclobut-2-en-1-imines (Alk = Me, Et, Bu) were synthesized from 1,3-dilithio-3-phenylpropyne, methyl isothiocyanate, and alkyl halides, and their fragmentation under electron impact was studied. Primary decomposition of the molecular ions of 2-aminothiophenes is determined by the localization of a radical cation center on the nitrogen atom, and it follows a path typical of alkyl(aryl)amines with elimination of hydrogen atom or methyl or propyl radical from the α-carbon atom in the N-alkyl substituent. Fragmentation of the iminothietanes involves cleavage of the four-membered ring in half to give neutral MeNCS molecule and 1-alkyl-1-phenylallene radical cation. Alkylsulfanyl(imino)-cyclobutenes undergo cleavage at the sulfur-containing side chain according to general relations holding in the fragmentation of alkyl sulfides.     

Stereochemical effect on biological activities of new series of piperidin-4-one derivatives

New series of (2S,3R,4S,6R)-3-methyl-4-alkyl-2,6-diarylpiperidin-4-ol were synthesised by the reduction of cis-3-alkyl-2,6-diarylpiperidin-4-one using Grignard reagent. The structural assignments and conformational studies of the synthesised compounds were established based on the IR, ¹H NMR, ¹³C NMR, NOESY and mass spectral studies. Their stereochemical effect on antibacterial, antifungal and anthelmintic activities was studied.     

A simple and efficient approach for the synthesis of a novel class aliphatic 1,3,4-thiadiazol-2(3H)-one derivatives via intramolecular nucleophilic substitution reaction

In this study, we synthesized a new series of substituted aliphatic 1,3,4-thiadiazol-2(3H)-one derivatives (6-24) in yields ranging from 42 to 70% with an interesting mechanism that involves internal nucleophilic substitution followed by an S_N2-type nucleophilic substitution. First, 1-(4-chlorophenyl)-2-((5-methyl-1,3,4-thiadiazol-2-yl)thio)ethanone (3) was synthesized from the reaction of 5-methyl-1,3,4-thiadiazole-2-thiol (1) with 2-bromo-1-(4-chlorophenyl)ethanone (2) in the presence of potassium hydroxide. Then, 1-(4-chlorophenyl)-2-((5-methyl-1,3,4-thiadiazol-2-yl)thio)ethanol (4) was synthesized by a reduction reaction of this compound using NaBH₄. Finally, 5-methyl-3-alkyl-1,3,4-thiadiazol-2(3H)-one derivatives (6-24), which are the target compounds, were synthesized from the reaction of this compound (4), which is a secondary alcohol with various alkyl halides (5a-n) in the presence of sodium hydride (NaH). This study presents an interesting reaction mechanism related to the synthesis of aliphatic 1,3,4-thiadiazol-2(3H)-one derivatives that is not recorded in the literature.     

Synthesis and characterization of the first azastibatranes and azabismatranes

Syntheses of title compounds, viz. N(CH2CH2NR)3E (1, E = Sb, R = Me; 4, E = Bi, R = Me; 6, E = Sb, R = SiMe3; 8, E = Bi, R = SiMe3), by the reaction of E(NAlk2)3 (3, E = Sb, Alk = Et; 5, E = Bi, Alk = Me) with N(CH2CH2NMeH)3 (2) or N(CH2CH2NSiMe3H)3 (7) are reported. The reactions of SbCl3 with N[CH2CH2N(Me)Li]3 or N[CH2CH2N(SiMe3)Li]3 and BiCl3 with N[CH2CH2N(SiMe3)Li]3 resulted in compounds 1, 6, and 8, respectively. Composition and structures of all novel compounds were established by 1H and 13C NMR spectroscopy and mass spectrometry. The X-ray structural study of 8 clearly indicated the presence of transannular interaction BiNdat in this compound, while 6 possesses a long Sb...Ndat distance. The structural data obtained from geometry optimizations on 6 and 8 reproduce experimental trends, i.e., a decrease in the E-Ndat distance from Sb to Bi. The values of electron density in E-Ndat critical point and the Laplacian of charge density for 8 indicate that a closed-shell interaction exists between the metal atom and Ndat atom.     

Ansa-茂锆催化剂对乙烯/1-辛烯共聚合研究

乙烯与α 烯烃共聚合可制得线性低密度聚乙烯等重要塑料产品．用茂金属催化剂与甲基铝氧烷（ＭＡＯ）助催化剂合成的乙烯／α 烯烃共聚物具有共单体分布均匀，分子量分布窄等特点，其性能比传统的Ｚｉｅｇｌｅｒ Ｎａｔａ催化剂体系所得共聚物优越．茂金属化合物的结构...     

Syntheses, structures, and reactivity of new pentamethylcyclopentadienyl-rhodium(III) and -iridium(III) 4-acyl-5-pyrazolonate complexes

New [CpM(Q)Cl] complexes (M = Rh or Ir, Cp = pentamethylcyclopentadienyl, HQ = 1-phenyl-3-methyl-4R(C=O)-pyrazol-5-one in general, in detail HQ(Me), R = CH(3); HQ(Et), R = CH(2)CH(3); HQ(Piv), R = CH(2)-C(CH(3))(3); HQ(Bn), R = CH(2)-(C(6)H(5)); HQ(S), R = CH-(C(6)H(5))(2)) have been synthesized from the reaction of [CpMCl(2)](2) with the sodium salt, NaQ, of the appropriate HQ proligand. Crystal structure determinations for a representative selection of these [CpM(Q)Cl] compounds show a pseudo-octahedral metal environment with the Q ligand bonded in the O,O'-chelating form. In each case, two enantiomers (S(M)) and (R(M)) arise, differing only in the metal chirality. The reaction of [CpRh(Q(Bn))Cl] with MgCH(3)Br produces only halide exchange with the formation of [CpRh(Q(Bn))Br]. The [CpRh(Q)Cl] complexes react with PPh(3) in dichloromethane yielding the adducts CpRh(Q)Cl/PPh(3) (1:1) which exist in solution in two different isomeric forms. The interaction of [CpRh(Q(Me))Cl] with AgNO(3) in MeCN allows generation of [CpRh(Q(Me))(MeCN)]NO(3).3H(2)O, whereas the reaction of [CpRh(Q(Me))Cl] with AgClO(4) in the same solvent yields both [CpRh(Q(Me))(H(2)O)]ClO(4) and [CpRh(Cl)(H(2)O)(2)]ClO(4); the H(2)O molecules derive from the not-rigorously anhydrous solvents or silver salts.     

NiII-mediated coupling between iminoisoindolinones and nitriles leading to unsymmetrical 1,3,5-triazapentadienato complexes

Treatment of nickel acetate Ni(OAc)2.4H2O with 2 equiv of various 3-iminoisoindolin-1-ones in a suspension of RCN in the presence of triethanolamine leads to the formation of the nickel 1,3,5-triazapentadienato complexes [Ni{NHC(R)NC(C6R1R2R3R4CON)}2] (1-17) isolated in good 50-83% yields. The reaction proceeds under relatively mild conditions (from 5 to 7 h at 25-115 degrees C, depending on the boiling point of the nitrile) and has a general character insofar as it was successfully conducted with various nitriles RCN bearing donor (R = Me, Et, Prn, Pri, Bun), weak donor (R = CH2Ph, CH2C6H4OMe-p), acceptor (R = CH2Cl), and strong acceptor (R = CCl3) groups R of different steric hindrance and also with the nonsubstituted iminoisoindolinone (3-iminoisoindolin-1-one) or the iminoisoindolinones bearing donor methyl (3-imino-5-methylisoindolin-1-one) or acceptor fluoro (4,5,6,7-tetrafluoro-3-iminoisoindolin-1-one) groups in the benzene ring.