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烯烃氢甲酰化反应(Hydroformylation),又称OXO合成,是指烯烃与合成气(CO和H2)在催化剂的作用下生成多一个碳原子的正构醛(n-alde-烯烃氢甲酰化反应最早是Roelen[1](1897~1993)于1938年在德国鲁尔化学公司从事费托合成中发现的.目前,该反应以每年800~900万吨的产量成为当今世界最重要的有机化工工艺[2],其产品遍及各种不同碳数的醛和醇,其中最主要的除由丙烯出发合成丁、辛醇外,还有以高碳烯烃为原料的C8-11增塑剂醇和C12-18的表面活性剂醇,被广泛用于增塑剂、织物添加剂、表面活性剂、药物中间体、溶剂和香料等精细化工领域[3,4].均相氢… 相似文献
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采用应力松弛实验及Haward模型, 研究了增塑剂含量、填料[CaCO3、炭黑(CB)]和丁腈橡胶(NBR)对软质聚氯乙烯(PPVC)的分子链缠结网络结构、分子链滑移及Gaussian模量的影响. 结果表明, 在PPVC主网络达到极限伸长之前, PPVC材料的粘弹行为能很好地符合Haward模型. 增塑剂、CaCO3和CB虽然不改变主网络的缠结结构, 并且主网络的极限伸长不变, 但增塑剂可以降低主网络的网链密度, 而CaCO3和CB可以提高主网络的网链密度; 同时增塑剂可减弱次级网络, 增大PVC分子链滑移, 使材料的Gaussian模量下降; CaCO3和CB可增强次级网络, 减小PVC分子链滑移, 使材料的Gaussian模量增加. NBR的加入可以改变主网络的缠结结构, 增加主网络的极限伸长; 既可降低PPVC主网络的缠结密度, 又可减弱次级网络, 使Gaussian模量降低. 相似文献
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1,3-丙二醇制备研究进展 总被引:1,自引:1,他引:0
1,3丙二醇(1,3-PDO)是一种重要的化工原料,可以作为溶剂、抗冻剂、增塑剂、乳化剂、防腐剂、洗涤剂和润滑剂等[1],在食品、医药、化妆品和有机合成中有着重要应用.此外,1,3-PDO还可以作为聚酯、聚醚和聚氨酯的单体. 相似文献
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为提高聚偏氟乙烯(PVDF)的熔融可加工性,将邻苯二甲酸二丁酯(DBP)、环丁砜(SFL)、三乙酸甘油酯(GL)以及碳酸丙烯酯(PC)等4种增塑剂分别用于PVDF的共混改性。采用示差扫描量热仪(DSC)、动态力学分析仪(DMA)以及电子拉力机等分别研究了PVDF-增塑剂共混试样的结晶性、相容性和力学性能。结果表明:当共混试样中增塑剂的质量分数小于10%时,增塑剂与PVDF具有很好的相容性,且共混试样具有很好的断裂强度和断裂伸长率;当增塑剂的质量分数大于10%时,增塑剂与PVDF的相容性变差,发生相分离。 相似文献
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作为功能材料的一个新品种,高分子固体电解质有极其广泛的应用前景[1]。近年来人们致力于对体系的改性研究[2-5],以提高电解质的室温离子电导率和获得适合的力学性能。本研究用水溶液聚合工艺,以过硫酸盐为引发剂,以丙烯酸为主单体、丙烯酰胺为第二单体,加入适当的增塑剂... 相似文献
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HTPB固体推进剂增塑剂选取分子模拟研究 总被引:3,自引:0,他引:3
固体推进剂中增塑剂要求同粘合剂体系相容性良好,并提高体系的低温性能.本文采用分子动力学(MD)方法,首先计算了端羟基聚丁二烯(HTPB)粘合剂及增塑剂癸二酸二辛酯(DOS)、己二酸二辛酯(DOA)、壬酸异癸酯(TOA)、邻苯二甲酸二丁酯(DBP)和邻苯二甲酸二辛酯(DOP)的溶度参数,以此从相容性角度选取推进剂增塑剂;计算数值基本吻合实验值,表明常用的增塑剂从相容性都能满足要求.其次模拟获取了HTPB及HTPB/增塑剂混合体系的比体积-温度关系得到了体系的玻璃化转变温度(Tg),揭示增塑剂对HTPB体系低温性能的影响.结果显示:(1)HTPB的Tg模拟值为202K,基本吻合实验值196K.(2)HTPB/DOS混合体系中,当增塑剂DOS的质量含量从12%、22%、29%到36%(摩尔含量分别为50%、66%、75%和90%)增加时,体系的Tg线性降低;TOA和DOP增塑的粘合剂体系(摩尔含量为75%)Tg也降低,而增塑剂DOA和DBP对体系的Tg影响不大.因此,基于相容性及提高粘合剂低温性能考虑,DOS、DOA和DOP作为HTPB的增塑剂优于TOA和DBP. 相似文献
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用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%. 相似文献
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Different approaches for the synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives from simple amino acids have been investigated. A library of 33 precursors for the preparation of N-hydroxy pyrazinones was obtained in moderate to good yields. 相似文献
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Uroš Grošelj Mojca Žorž Amalija Golobič Branko Stanovnik Jurij Svete 《Tetrahedron》2013,69(52):11092-11108
A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives. 相似文献
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The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp3)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp2)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp2)?H and aliphatic 1,5- and 1,6-C(sp3)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp3)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp2)?H insertion. 相似文献
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A general synthesis of previously unknown semicarbazone-based α-amidoalkylating reagents, 4-(tosylmethyl)semicarbazones, has been developed. The synthesis involved three-component condensation of semicarbazones of aliphatic or aromatic aldehydes with the same or other aldehydes and p-toluenesulfinic acid. The scope and limitations of this reaction were investigated. The compounds obtained were demonstrated to be an efficient α-(4-semicarbazono)alkylating agents. They were reacted with H- (sodium borohydride), O- (sodium methylate), S- (sodium phenylthiolate), N- (pyrrolidine, sodium succinimide), P- (trialkyl phosphites), and C-nucleophiles (sodium diethyl malonate) to give the corresponding products of the tosyl group substitution, 4-substituted semicarbazones, including analogues of nitrofurazone. Among the prepared compounds tested in vitro for antibacterial and antifungal activity, three nitrofuryl-containing semicarbazones exhibited high biological activities with minimum inhibitory concentration (MIC) values of 8–32 μg/mL. 相似文献
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A small library of new chiral bidentate hydroxyalkyl-imidazolium salts 1 is conveniently synthesized on multi-gram scale from inexpensive and commercially available chiral pool amino acids. The corresponding carbenes, generated by deprotonation of imidazolium salts 1, in combination with palladium(II) chloride were tested in the Mizoroki–Heck coupling reaction. The most significant results in terms of yields and reactivities were achieved with low catalyst loading. The catalytic activities of these imidazolium salts were also investigated in the asymmetric addition of diethylzinc to benzaldehyde. The use of MgO nanoparticles as an additive in conjunction with these ligands played a crucial role in increasing the efficiency of these reactions. 相似文献
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N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%). 相似文献
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Shashikant U. Dighe Surya K. Samanta Shivalinga Kolle Sanjay Batra 《Tetrahedron》2017,73(17):2455-2467
An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y1 and Y2. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones. 相似文献
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In this Letter, we described a facile method for constructing fused bicyclic 1-arylpyrazol-5-one ring system. We employed various methylene-containing carboxylic acids as the substrates and proved that the pyrazolone ring closure requires activated methylene group in intermediate II. Accordingly, a series of structurally diversified, fused bicyclic 1-arylpyrazol-5-ones was prepared in moderate to high yields using the requisite substrates. 相似文献
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The Langevin paramagnetic theory can’t describe the relation between magnetization of ferrofluids and applied magnetic field. The structuralization of ferrofluids, which is considered the main influence factor of the magnetization, is regarded. The part of magnetization works is deposited when the structure is forming. This action influences the magnetization of ferrofluids directly or indirectly. On the base of the “compressing” model, the Langevin function that usually describes the magnetization of ferrofluid is modified, and a well-fitted curve is obtained. An equation of the relation between the equivalent volume fraction after being “compressed” and the intensity of magnetic field is discovered, which approximately describes the process of magnetization. The relation between the approximate initial susceptibility and the volume fraction can be obtained from modified formula. 相似文献