丝光沸石上精萘的择形异丙基化反应

2,6-二异丙基萘(2,6-D IPN)是制备高级聚酯材料PEN和液晶聚合物的原料。该文以精萘和丙烯为原料,以水汽脱铝氢型丝光沸石(SDHM)代替传统的傅-克催化剂,在0.5 L高压釜中进行择形异丙基化反应,得到了高选择性和高收率的2,6-D IPN。不同来源的精萘中的含氮量对催化剂的活性产生很大影响。含氮量越低,异丙基化效果越好。为了减缓催化剂的失活,反应在氢氛下进行,以降低稠环芳烃的脱氢和结焦。和氮氛下的结果相比,氢氛下精萘的转化率和2,6-D IPN的产率均显著提高,其连续反应7釜的平均值分别达到90%和35%。     

Effects of reaction temperature on the isopropylation of biphenyl over H-mordenite

The effects of reaction temperature on the selectivity for bulk products and for encapsulated products in the pores were investigated in the isopropylation of biphenyl over a highly dealuminated H-mordenite under 0.8 MPa of propylene. The selectivity for 4,4'-diisopropylbiphenyl (4,4'-DIPB) in bulk products was changed with the increase of reaction temperature: it decreased with increasing that for thermodynamically stable 3,3'- and 3,4'-DIPB. However, the selectivity for 4,4'-DIPB in encapsulated products was as high as 85–90% between 200 and 350oC. These results show that H-mordenite catalyzes the isopropylation of biphenyl inside the pore with high shape selectivity at these temperatures, and that the decrease of the selectivity for 4,4'-DIPB in the bulk products is due to its isomerization to 3,3'- and 3,4'-DIPB on external acid sites. This revised version was published online in July 2006 with corrections to the Cover Date.     

3,3''-二氨基-4,4''-二羟基联苯的分析

采用高效液相色谱法，在C－18柱上，以甲醇－水（体积比为55：45）溶液为流动相，检测波长为265nm，测定了3，3‘-二氨基－4，4‘-二羟基联苯的含量。该法简便、快速，是监控反应的较好方法。     

4-甲氧基-3-卤代联苯的合成

以对甲氧基联苯胺为原料,在-5~0℃下进行重氮化,再与氯化亚铜或溴化亚铜在90℃发生Sandmeyer反应,得到4-甲氧基-3-卤代联苯,考察了原料配比、反应温度和反应时间等对反应的影响,并通过熔点、红外光谱、核磁共振波谱等对其进行了表征。研究结果表明,采用该方法合成的3-氯-4-甲氧基联苯的总收率为63%,3-溴-4-甲氧基联苯的总收率为51%。     

Shape-selective alkylation of biphenyl over mordenites: effects of dealumination on shape-selectivity and coke deposition

To understand the relationships between shape-selectivity and coke deposition in the alkylation of biphenyl over H-mordenite (HM), thermogravimetric analyses were examined for the catalyst after the reaction. The coke deposition during the catalysis was very severe over HM with low SiO/Al₂O₃ ratio, however, dealumination enhanced the decrease of coke deposition. Over highly dealuminated HM, volatile organic compounds, mainly biphenyl derivatives, were observed in addition to carbonaceous deposits. The deposits are produced from biphenyl derivatives on acid sites in the HM pore, and the ease of their formation is governed by acid site density and acid strength. The decrease of carbonaceous deposits and the increase of encapsulated biphenyl derivatives are related with the increase of both selectivity and yield of 4,4-diisopropylbiphenyl (4,4-DIPB). The increase of reaction temperature up to 250°C enhanced the catalysis over highly dealuminated HM, however, further increase of the temperature resulted in extensive decrease of the selectivity of 4,4-DIPB. Coke deposition also increased with the temperature although its level was low. The composition of 4,4-DIPB in encapsulated DIPB isomers remained as high as 80% in spite of a change of the distribution of bulk products.     

Shape-selective alkylation of biphenyl over mordenite: cerium exchanged sodium mordenite and unmodified H-mordenite with low SiO2/Al2O3 ratio

Liquid phase isopropylation of biphenyl with propylene was studied over a cerium exchanged sodium mordenite (Ce/NaM25) and a H-mordenite (HM25) with the same SiO₂/Al₂O₃ ratio of 25. Shape-selective catalysis occurred to give 4,4-diisopropylbiphenyl (4,4-DIPS) in high selectivity over Ce/NaM25 under any propylene pressures. HM25 gave 4,4-DIPS shape-selectively under high propylene pressures. However, the reaction was severely deactivated at a conversion of ca. 60% under such a low pressure as 0.8 kg/cm² because of coke formation in the pore. The yields of 4-isopropylbiphenyl (4-IPBP) and 4,4-DIPB decreased with the increase of those of 3-IPBP and 3,4-DIPB because of non-selective alkylation and isomerization at external acid sites that are alive in spite of severe deactivation. No significant isomerization of 4,4-DIPB over Ce/NaM25 was observed even at low propylene pressure. In the case of HM25, the isomerization of 4,4-DIPB to 3,4-DIPB occurred significantly under low propylene pressures, while it decreased under high pressure. These differences are ascribed to the differences of nature of acid sites between Ce/NaM25 and HM25 zeolites.     

Synthesis of AlPO4 Molecular Sieves with AFI and AEL Structures by Dry-Gel Conversion Method and Catalytic Application of Their SAPO Counterparts on Isopropylation of Biphenyl

AlPO₄-5 and AlPO₄-11 were synthesized by dry-gel conversion (DGC) method. Steam-assisted conversion (SAC) and vapor-phase transport (VPT) techniques were applied for this purpose. The synthesis was successful in presence of a certain minimum amount of external bulk water, without which the crystallization failed. Crystallization by VPT method was slower than corresponding SAC and HTS method. SAPO analogs of the samples, SAPO-5 and SAPO-11 were also synthesized by DGC method. Samples made by DGC methods had higher yield than the conventional hydrothermal synthesis (HTS); otherwise the samples showed similar characteristics as that made by HTS. XRD, SEM and N₂-adsorption results showed high crystallinity and purity of the samples made by DGC, and ²⁷Al MAS NMR spectra indicated the tetrahedral framework nature of Al. SAPO-5 and SAPO-11 were tested for their catalytic activity in isopropylation of biphenyl, and in terms of conversion and selectivity, SAPO-5 was found to be suitable for this application.     

2-(3-氟-4-苯基)苯丙酸合成

二步法合成2-（3-氟-4-苯基）苯丙酸，收率50％（以4-溴-2-氟联苯计）     

酸碱复合改性丝光沸石催化4-异丙基联苯异丙基化

采用酸碱复合改性的方法,制备了同时具有微孔和介孔孔道的丝光沸石,用于固定床4-异丙基联苯的异丙基化反应。通过X射线衍射(XRD)、透射电子显微镜(TEM)、NH3程序升温脱附(NH3-TPD)、N2物理吸附脱附等方法对改性丝光沸石进行表征。结果表明,碱改性处理调变了丝光沸石的孔道结构和酸性质,同时保持了其MOR拓扑结构,提高了4-异丙基联苯的转化率和反应的稳定性。碱处理后再进行酸处理,可以有效清除碱处理过程中产生的非骨架铝物种和样品外表面的酸中心,提高目的产物4,4'-二异丙基联苯的选择性。     

4,4'-二氯甲基联苯的合成研究

本文通过催化剂种类与用量、溶剂、反应温度及时间的筛选与优化,使4,4'-二氯甲基联苯的收率达到87.8%,纯度达到98.0%,同时消除了有害物质二氯甲醚对环境的影响.     

一种合成4-氰基联苯的方法

以联苯为原料,经傅克酰基化、氨解、脱水三步反应合成4-氰基联苯,不产生含氰废水。4-氰基联苯的总收率达到70.70%,HPLC含量达到98%以上。     

择形烷基化合成4,4'-二烷基联苯的研究进展

综述了用沸石分子筛作催化剂,择形烷基化合成4,4’-二烷基联苯的研究进展。重点介绍了近年来对两种催化剂HM和HZSM-5的改性研究,催化烷基化反应合成4,4’-二异丙基联苯和4,4’-二甲基联苯所取得的研究成果。明确了今后择形烷基化合成4,4’-二烷基联苯的研究方向。     

3-甲基-4-丁酰氨基-5-氨基苯甲酸甲酯的合成

3-甲基-4-丁酰氨基-5-氨基苯甲酸甲酯是重要的药物中间体。以3-甲基-4-丁酰氨基苯甲酸甲酯为原料，经硝硫混酸硝化、铁粉还原得到目标化合物3-甲基-4-丁酰氨基-5-氨基苯甲酸甲酯，总收率72％。研究了硝硫混酸配比、硝化反应时间、还原反应温度、还原反应时间等因素对产物收率的影响，该工艺具有生产成本低，产品质量稳定，收率高的优点。     

一种新型吡唑烷酮的合成及晶体结构

以对甲氧基肉桂酸甲酯与对异丙基苯肼为原料,合成得到了1-（4-异丙基苯基）-5-（4-甲氧基苯基）-3-吡唑烷酮,利用溶剂挥发法得到该化合物的单晶。同时对其进行了元素分析、核磁表征和X-射线单晶衍射分析。晶体结构分析结果表明：该晶体属于单斜晶系,P2（1）／n空间群,a=14．737（3）nm,b=7．1490（14）nm,c=17．493（3）°nm,d=90．00（3）°,β=112．03（3）°,γ=90．00°,Dc=1．258g／cm^3,Z=4,F（000）=664,μ=0．087×10^-6nm^-1,最终偏差因子分别为R=0．1473,wR=0．2097。分子内氢键和分子间作用力使得晶体结构稳定性增强。     

对氯-γ-溴丙苯的合成

提出了对氯－r-溴丙苯的合成方法,以对氯氯为原料制取对氯苄基氯化镁,通过镁过量解决了在四氢呋喃中的偶联问题,提高了格氏试验剂的收率,此格氏试剂与环氧乙烷反应得到氯－r-苯丙醇,然后在三氯甲烷助溶剂作用下,与过量的氢溴酸反应得到对氯－r－溴丙苯,文中优化得出了最佳合成条件,为工业化生产提供了理论依据。     

纳米固体超强酸SO2-4/Fe2O3催化合成尼泊金酸丁酯

以纳米固体超强酸SO2-4/Fe2O3为催化剂,催化尼泊金酸与正丁醇的酯化反应,合成尼泊金酸丁酯.较适宜的反应条件为:尼泊金酸25 mmol,n(尼泊金酸):n(正丁醇)=1:4,催化剂加入量为反应物总质量的2%,甲苯5 mL,温度(122～124)℃,反应4 h,酯化率达92.4%.     

1-(4-氯苯基)-3-吡唑醇的合成

[方法]1-(4-氯苯基)-3-吡唑醇是一种重要农药中间体,以对氯苯肼为原料经环合、氧化,合成1-(4-氯苯基)1-3-毗唑醇.[结果]在优化的反应条件下,1-(4-氯苯基)-3-吡唑醇的反应总收率为72.5%(以对氯苯肼计),含量为99.2%,其结构经红外和氢谱核磁分析确证.[结论]该工艺具有反应条件温和、产品收率高等优点,适合工业化生产.     

Selective Isopropylation of Isobutylbenzene over H-Mordenite in Supercritical CO2 Medium: Remarkable Enhancement in Catalytic Activity and Selectivity for 4-Isobutylcumene

Remarkable enhancement in the catalytic activity and selectivity for the formation of 4-isobutylcumene (4-IBC) was observed in the isopropylation of isobutylbenzene (IBB) over highly dealuminated H-mordenite in supercritical CO₂ (sc-CO₂) medium. Thermogravimetric analyses confirm that reduced coking of the catalysts in sc-CO₂ medium and stronger acid sites in dealuminated H-mordenite (MOR) are the key factors for superior activity and selectivity for 4-IBC.     

间溴苯氧丙酸与7-溴苯并二氢吡喃-4-酮的合成

以间溴苯酚和3-溴丙酸为原料,合成了间溴苯氧丙酸,并以间溴苯氧丙酸为原料,进一步合成了7-溴苯并二氢吡喃-4-酮。探讨了投料比、反应时间、反应温度、氢氧化钠的质量分数和加料顺序等因素对间溴苯氧丙酸收率的影响。适宜的反应条件为:n(间溴苯酚)∶n(氢氧化钠)∶n(3-溴丙酸)=1∶1∶1.3,反应温度95℃,氢氧化钠的质量分数8%,反应时间7 h,间溴苯氧丙酸收率71.4%。以间溴苯氧丙酸为原料,以85%的收率合成了7-溴苯并二氢唑喃-4-酮。     

1-(5-(4-氯苯基)-1-(2,4-二氯苯基)-4-甲基-1H-吡唑-3-基)-3-(吡啶-3-基甲基)脲的合成

以5-(4-氯苯基)-1-(2,4-二氯苯基)-4-甲基-1H-吡唑-3-甲酸与二氯亚砜为起始原料,经酰氯化反应、酰胺反应、霍夫曼重排以及水解反应生成中间体5-(4-氯苯基)-1-(2,4-二氯苯基)-3-氨基-4-甲基-1H-吡唑,再经过与氯甲酸苯酯反应、胺酯交换反应得到标题化合物,其结构经1HNMR、MS谱确证,总收率26.9%。