3-吡啶甲酰基吲哚类化合物的合成研究

为了发展一种高效简便合成标题化合物的方法,使用N-烷基芳香胺和吡啶甲酰基烯胺作为反应底物,通过考察催化剂、氧化剂、反应温度及溶剂对反应的影响来获得最优的反应条件。在最优反应条件下,吡啶甲酰基烯胺的sp² C—H键与N-烷基芳香胺的邻位sp² C—H键通过交叉氧化脱氢环化反应,一步即高区域选择性地合成了7个标题化合物。产物均通过¹HNMR、¹³CNMR和HR-MS等分析方法进行结构表征。     

2-氨基取代苯甲醛化合物的制备方法

正本发明提供了一种苯甲醛的制备方法,其中氨基键合在2位,卤素基或烷氧基键合在3位,氢原子、烷基、卤素基、烷氧基或氰基分别键合在4、5和6位,所述方法包括:制备苯甲醛,其中卤素基或烷氧基键合在3位,氢原子键合在2位,氢原子、烷基、卤素基、烷氧基或氰基分别键合在4、5和6位,使锂化反应最活跃在2位;缩醛保护苯甲醛中的甲酰基;     

环氧化合物改性侧链氨基聚硅氧烷的研究

以5种单官能缩水甘油醚——腰果酚缩水甘油醚（NC-513）、烯丙基缩水甘油醚（AGE）、苄基缩水甘油醚（692）、正丁基缩水甘油醚（660）及甲基丙烯酸缩水甘油酯（GMA）和侧链氨基聚硅氧烷为原料,通过环氧基与氨基的反应对侧链氨基聚硅氧烷进行改性。研究了不同反应条件下,改性聚硅氧烷的凝胶行为,表征了改性聚硅氧烷的结构。结果表明,NC-513与侧链氨基聚硅氧烷的反应活性最大;且室温以上时,改性聚硅氧烷凝胶的形成不受反应溶剂及原料反应官能团量之比的影响,所形成的凝胶为氢键物理交联;当温度升高时,会伴有羟基缩合的化学交联,烯键不与氨基反应。由于GMA中烯键和环氧基均与氨基反应,故形成化学交联凝胶。AGE、692、660改性聚硅氧烷在有溶剂的体系形成凝胶,在无溶剂情况下不形成凝胶。     

长链烷烃改性氨基硅油的表征

以硬脂酸、叠氮化钠、三苯基膦及N-氯代丁二酰亚胺为原料,通过Staudinger反应及Curtius重排制备十七碳单异氰酸酯。利用十七碳单异氰酸酯的异氰酸酯基高反应活性,对氨丙基硅油进行长链烷基改性。通过控制投料比,可以调节氨丙基硅油侧链上长链脲基的引入量。以FT-IR、^1H NMR对长链脲基改性氨基硅油进行结构表征,证实得到了预期的目标产物。     

对煤分子中活性基团氧化机理的分析

根据煤分子结构的研究成果,推断桥键中的次甲基醚键、α位碳原子带羟基和带支链亚甲基的次烷基键、与两个芳环相连的次甲基键,以及侧链中的甲氧基、醛基、α位碳原子带羟基的烷基为常温常压下发生煤氧复合的活性结构。其氧化活性以醛基侧链、次甲基西边键、α位带羟基的次烷基键、α位带亚甲基的次烷基键、甲氧基、α位带羟基的烷基侧链、与两个芳环相连的次甲基键的顺序排列。由于氧分子存在两个未饱和分子轨道,煤分子活性基团在共轭效应和诱导效应作用下,呈现部分未成对的电子云进入氧分子轨道产生化学吸附,进而有部分发生各步氧化反应,放出热量。根据每步反应的键能变化,采用加权平均法可推算出煤氧复合每产生1mol CO,CO2和H2O的热效应值。由于煤中七种活性结构的氧化性不同及不同种类煤中各种活性结构的数量不同,煤氧化反应放出的热量不同,煤自然性也就不同。     

苯甲酸衍生物类神经氨酸酶抑制剂的合成及活性评价

以4-氨基-3-碘苯甲酸甲酯(Ⅴ)为原料,经过偶联、酰化、水解等反应得到苯甲酸衍生物类流感病毒神经氨酸酶抑制剂Ⅵ~Ⅸ,化合物Ⅴd[4-乙酰胺基-3-(2-乙基-1-丁烯基)苯甲酸甲酯]经过氧化、还原、水解反应得到化合物Ⅹ~Ⅻ,结构经1HNMR、13CNMR、MS确证,并用化学荧光法测定对神经氨酸酶的抑制率,测试选用流感病毒菌株H3N2(California/04),H1N1(California/99)和B(Shanghai/02)。结果显示:在Ⅵ~Ⅸ中,苯环C3位置侧链越大,化合物的活性越低,其中,化合物Ⅸ[4-乙酰胺基-3-(2-羟基-2-乙基丁烷基)苯甲酸]的活性最强,对H3N2、H1N1、B的半数抑制浓度分别为1.0、2.1、1.6μmol/L;Ⅹ~Ⅻ中,苯环侧链α位碳上的羟基比β位活性增强,在苯环侧链α位的碳上含有单羟基的化合物Ⅻ[4-乙酰胺基-3-(2-乙基-1-羟基丁烷基)苯甲酸]具有对两种A型流感病毒最强的活性,半数抑制浓度分别为0.15和0.20μmol/L。     

木质素催化氧化过程中典型化学键断键研究

木质素是自然界中含量最丰富的可再生芳香资源,各芳香基本单元通过C—O和C—C键连接。氧化解聚能显著降低化学键键能,对木质素结构中C—C键的裂解尤为有效,并生成芳香醛、酸、酮等高度功能化的高值产物。针对不同键的断裂能定向制备所需产物,如C_β—O键断裂易生产苯酚类以及酮类产物,C_α—C_β键断裂易制备芳香醛类和羧酸类产物,C_α—C_ary键断裂能有效去除侧链烷基等。文章重点从断键路径的角度综述了以上三种化学键的研究现状,同时介绍了各种化学键断裂的催化剂研究以及真实木质素氧化解聚进展。在此基础上,展望了未来木质素氧化解聚的研究方向,以实现木质素的高价值转化。     

含两个识别点的侧链准聚轮烷的制备

合成了侧链含烷基链(C7)及偶氮基团(Azo)两个疏水基团修饰的聚合物4,并基于环糊精与两个疏水基团C7、Azo的不同结合能力,制备了含两个识别点的侧链准聚轮烷。首先,在聚合物4的溶液中加入α-环糊精(α-CD),α-CD分别包结在C7及Azo部分,得到了侧链准聚轮烷;第二步,在365nm的紫外光光照下,聚合物4侧链端基的trans-Azo异构为cis-Azo,α-CD从Azo部分解离,但α-CD仍包结在C7部分,得到了侧链聚轮烷;第三步,在侧链聚轮烷溶液中加入β-环糊精(β-CD),β-CD包结在cis-Azo部分,得到了α-CD、β-CD分别包结两个疏水识别点的侧链准聚轮烷。     

C8芳烃中乙苯在纳米HZSM-5沸石上选择性催化裂解

本文采用自装的小型固定床常压反应器为反应器,以纳米HZSM-5沸石为催化剂,对混合C8芳烃中的乙苯选择性催化裂解脱烷基反应进行了研究。结果表明,反应温度对于各种碳八芳烃的异构体互相转化有重要影响。通过实验可知乙苯催化裂解后脱烷基反应的最小温度应是450-480℃左右。高的反应温度有利于提高乙苯转化率,但反应温度过高会导致乙苯侧链裂解,并产生二甲苯脱烷基等副反应。根据钠离子改性和NH3-TPD谱图、吡啶红外光谱表征发现,乙苯分子催化裂解脱烷基反应需要强酸中心。但过强的酸中心可能会加重乙苯侧链裂解反应和二甲苯脱甲基、氢转移等副反应。     

氟化过氧化物（二）

5．3氟烷基酰基过氧化物的热分解全氟烷酰基过氧化物的热分解的报道比氟化芳酰基过氧化物多。这是由于全氟烷基酸基过氧化物的分解与相应的无氟过氧化物不同。而氟芳酰基过氧化物与无氟芳酰基过氧化物表现了相似的反应性。Swain等人指出推电子基团的引入加强了芳酸基过氧化物的分解速率。苯环上推电子基团的影响超过了吸电子基团碳基基团的影响。因此，O－O键端基上氟烷酷基基团（RFC—O）应加强了过氧键的热稳定性。然而，Zhao等人和Sawada等人分别报道观察到全氟烷酚基过氧化物（如全氟丁酚基过氧化物和三氟乙酸基过氧化物）的热分解…     

轮胎胶应力诱导脱硫化及PE-HD动态交联热塑性弹性体制备

采用在废旧轮胎胶粉(GTR)与高密度聚乙烯(PE-HD)的熔融挤出过程中提高双螺杆挤出机螺杆转速的高剪切应力诱导方法,研究了双螺杆挤出机的螺杆转速、挤出反应温度及脱硫促进剂仲丁醇、烷基酚多硫化物(420或450)和正丁胺对轮胎胶脱硫共混物的凝胶含量、熔体流动速率、溶胶红外吸收光谱及轮胎胶脱硫共混物/三元乙丙橡胶(EPDM)动态交联热塑性弹性体力学性能的影响。结果表明:高转速同向双螺杆挤出机的高剪切作用可诱发废旧轮胎胶共混物中交联网络的断链和解交联反应,引起脱硫共混物凝胶含量的下降、未熔融凝胶颗粒尺寸的减小及熔体流动速率的增加;4种促进剂均具有明显促进脱硫反应的作用,其中450或正丁胺的促进脱硫效果较好,并引起脱硫共混物凝胶含量下降、熔体流动速率上升及动态交联热塑性弹性体力学性能的明显改善;当以正丁胺为脱硫促进剂时,最佳脱硫反应条件(240℃和1000r/min)下,脱硫共混物/EPDM动态交联热塑性弹性体的拉伸强度和断裂伸长率分别达到12.5MPa和440.6%。     

杏壳木质素的结构表征及其热解特性研究

为研究杏壳木质素的结构、热解特性及其产物的生成规律,通过硫酸脱除法从杏壳中分离出杏壳木质素,并通过红外光谱(FT-IR)和核磁共振(NMR)对其结构组成进行表征,利用热重及热重-红外联用分析研究其热解产物生成特性。研究结果表明：硫酸脱除法得到的杏壳木质素得率为30.42%,红外光谱图显示有较强的紫丁香基峰,还有一定量的愈创木基,二维核磁共振图谱表明杏壳木质素中有紫丁香基(S)、愈创木基(G)和对羟基苯基(H)3种木质素结构单元,属于SGH型木质素。热重及热重-红外联用分析表明杏壳木质素热解过程主要分为3个阶段,主要热解阶段发生在150~650 ℃之间的较宽温度范围内,360 ℃时热失重速率最大,热解产物主要为H₂O、CO、CO₂、CH₄以及醇、醛、酚、酸等。杏壳木质素中苯丙烷侧链上醚键和苯环间醚键断裂及挥发分二次裂解使CO的析出温度范围较宽,在200~700 ℃之间;羧基和羰基等官能团不稳定易断裂和重整,使CO₂的析出温度范围较窄,在250~650 ℃之间;苯丙烷侧链的断裂和苯环上甲氧基官能团的去甲基化反应,以及芳香环的深度断裂,使CH₄的析出在400和600 ℃时呈现2个峰值。     

Viscoelastic properties of (cellulose oligo-oxymethylene ether) acylates with bulky side chain

A series of (cellulose oligo-oxymethylene ether) acylates (COAs) are characterized by the presence of the micro-Brownian motion of the side chain (β process) which appears separately from that of the main chain (α process). Both the alpha; and β processes are largely affected by the kind of acyl groups introduced in the side chain. To clarify the effect of the acyl group on these processes, we investigated the dynamic mechanical properties of newly prepared COAs with acyl side chain, bulky in chemical structure (iso-butyrate, privalate, and benzoate) in relation to those for COAs with linear acyl side chain (acetate, butyrate, and valerate). By substituting bulky acyl isomer for linear acyl group in COAs, we observed that the temperature region of both the α and β processes moved to higher temperature. Furthermore, with an increase in molecular size of bulky acyl group, the β region shifts were much larger than the α region, indicating that the mobility of the side chain became comparable to that of the main chain. Finally, when such a large bulky group, for example, benzoate was introduced, the micro-Brownian motion of the side chain prior to that of the main chain ceased. The apparent activation energy for a third process (γ) due to the motion of the oligo-oxymethylene parts in the side chain was estimated to be 10.3 kcal/mol.     

A novel synthesis of polymers with anthracene and dihydroanthracene subunits in the main chain

A new polycondensation method to connect redox-active and chromophoric subunits by forming a C-C bond and leading to a polyhydrocarbon is described. 1,ω-bis(9,10-Dihydro-9-anthry)alkanes with various alkylene spacers can be deprotonated by butyllithium to afford a monoanion in each dihydroanthracene moiety. Alkylation with dielectrophiles such as dibromoalkanes yields soluble polymers with dihydroanthracene units in the main chain. The reaction proceeds regioselectively in the 9,10-position. Aromatization generates a polymer with anthracene units. The molecular weights are determined by GPC up to M?_n = 10 000. To prove the structure and to calibrate the GPC, suitable model compounds were synthesized.     

Photolysis of poly(benzyl methacrylate)s and poly(benzyl acrylate)s in solution and films

Methacrylate and acrylate copolymers containing benzyl or 1‐phenylethyl groups and their monomeric model compounds were irradiated with a 254‐nm light in CH₂Cl₂ and solid films. Low molecular weight and polymeric products were analyzed by gas chromatography (GC) and NMR spectroscopy, respectively, and main‐chain scission efficiencies were determined by gel permeation chromatography (GPC). The results indicate that the ester bond cleavage in the side chain produces alkyl radicals in the main chain, leading to main‐chain scission and crosslinking. The higher stability of tertiary alkyl radicals formed in methacrylate polymers lead to the predominant main‐chain scission in solution. On the other hand, acrylate polymers were less susceptible to photodegradation. The degradabilities of the polymer films reflected those of the polymer solutions, although crosslinking preferentially occurred. The distinct effect of oxygen on the degradation was also observed in solution and films. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 2227–2236, 2001     

Termination rate constant in butyl acrylate batch emulsion polymerization

Summary The kinetics of seeded batch emulsion polymerization of n-butyl acrylate (BA) have been investigated at 50°C using potassium persulfate (KPS) as the thermal initiator. The variations in the average number of radicals per particle (ñ) and termination rate constant (k_t) have been determined as a function of conversion for particles of different sizes using established kinetic equations. Contrary to expectations, the values of ñ were found to be unusually high and the values of k_t were found to be very low for all the reactions studied. The high values of ñ are consistent with the low rates of termination. An explanation has been proposed for the low values of k_t based on preliminary computations of the energy barrier for rotation about the terminal C-C bond of the polymer chain end of polybutyl acrylate (PBA).     

NHPI催化分子氧选择性氧化木质素模型分子中的C-C键

以1,2-二苯乙烷为模型分子,考察了N-羟基邻苯二甲酰亚胺（NHPI）对分子氧氧化断裂木质素分子中C-C键的催化作用,比较了Cu、Co和Mn的多种可溶性盐对NHPI催化活性的促进作用,探究了工艺条件对1,2-二苯乙烷氧化的影响规律。结果表明：NHPI能够在温和条件下催化分子氧氧化1,2-二苯乙烷中的C-C键断裂生成苯甲醛和苯甲酸。可溶性的Cu、Co和Mn盐都具有助催化作用,其中乙酸锰的助催化作用最强。确定了二苯基乙酮为氧化的初级反应产物。发现提高反应温度、增加乙酸锰用量以及延长反应时间,有利于C-C键的氧化断裂和提高小分子产物的选择性。优化的反应条件为NHPI为底物物质的量的10%,乙酸锰和NHPI之比为1：10,反应温度90℃,氧气分压1.0 MPa,反应时间8 h,C-C键的氧化断裂产物苯甲醛和苯甲酸的总选择性可达76.5%。     

Synthetic and mechanistic studies of the cycloisomerization and cyclization/hydrosilylation of functionalized dienes catalyzed by cationic palladium(II) complexes

This Account describes the development and mechanistic study of the cycloisomerization and cyclization/hydrosilylation of functionalized dienes catalyzed by cationic palladium(II) complexes. These transformations are characterized by good functional group compatibility, high regio- and stereoselectivity, and low air- and moisture-sensitivity. Mechanistic studies of palladium phenanthroline-catalyzed diene cycloisomerization and cyclization/hydrosilylation established mechanisms involving C-C bond formation via intramolecular carbometalation of an alkyl olefin chelate complex, which was directly observed in the context of cyclization/hydrosilylation.     

Structure-activity relationships for analogs of (+)-(E)-endo-Β-bergamoten-12-oic acid,an oviposition stimulant ofHelicoverpa zea (Boddie)

-Bergamotenoic acid, a compound previously shown to stimulate oviposition inH. zea, was converted into a set of bicyclic analogs and tested with a set of acyclic side chain analogs to ascertain the molecular structure that maximizes insect behavioral response. While changes in the bicyclic ring elicited no variation in response, alteration in the side chain structure of-bergamotenoic acid resulted in significant changes in moth preference. Free rotation about the C-C bond proximal to the carboxylic acid group appears to be an important structural factor, since saturation of the side chain double bond significantly increased activity. The carboxylic acid group seems to be required for strong oviposition stimulation, since analogs lacking the carboxylic acid group exhibited no significant oviposition activity. Oviposition preference ofH. zea was also influenced by the length of the hydrocarbon chain to which the carboxylic acid is attached. While hexanoic acid was found inactive, the ovipositional preference for the heptanoic and octanoic acids was greatest for the one 8-carbon tested. This and other work suggest that carboxylic acids of specific chain lengths influence the oviposition behavior of bothHelicoverpa andHeliothis species and may be associated with host-plant selection. The potential use of this information in designing integrated pest management strategies for control ofH. zea is discussed.     

长链烷基咪唑类离子液体对等规聚丙烯熔融接枝丙烯酸的影响

制备了一系列含不同碳原子数的强极性咪唑类离子液体([Cnmim]Cl)和弱极性的([Cnmim]PF6),并将其应用于等规聚丙烯(i-PP)熔融接枝丙烯酸(AA),考察了离子液体极性强弱和烷基链碳数对接枝率和副反应的影响。结果表明:强极性的[Cnmim]Cl对接枝率没有明显提高的作用,而弱极性的[Cnmim]PF6可显著提高接枝率,且烷基链越长,AA的接枝率越高;长链烷基咪唑类离子液体可显著降低接枝过程中副反应的发生,[Cnmim]PF6在降低副反应方面的作用优于[Cnmim]Cl。DSC结果表明弱极性的[Cnmim]PF6可以很好对等规PP进行溶解,随烷基碳数和用量的增多,溶解效果越好,强极性的[Cnmim]Cl溶解效果相对差些;相比未接枝PP,接枝物熔融温度较接近,而结晶温度和结晶度都降低。XRD分析结果表明在离子液体作用下所得到的接枝物中没有β晶型的生成。