不同有机胺对合成杂原子Ga—SI—ZSM—5分子筛的影响

考察了几种有机铵作引导剂对以水玻璃为硅源、硝酸镓为镓源合成Ｇａ－Ｓｉ－ＺＳＭ－５分子筛的影响。结果表明，合成体系的最佳碱度与有机胺有关，不同有机胺的合成效果相关很大，以正丁胺作引导剂可获得高结晶度的分子筛产物。通过与合成Ａｌ－Ｓｉ－ＺＳＭ－５的比较和一些条件试验，探讨了有机胺的作用，并对分子筛的形成过程进行了合理的推测。     

Na，NBA－Ga－Si－ZSM－5杂原子沸石分子筛的表征

Ｎａ，ＮＢＡ┐Ｇａ┐Ｓｉ┐ＺＳＭ┐５杂原子沸石分子筛的表征高志贤程昌瑞谭长瑜李源（中国科学院山西煤炭化学研究所，太原０３０００１）关键词Ｇａ－Ｓｉ－ＺＳＭ－５沸石分子筛，正丁胺，表征，模板作用近年来的研究结果表明，使用不同类型的有机胺或醇作引导剂，甚...     

有机硅结构导向剂法合成ZSM-5分子筛

新型分子筛的合成一直是分子筛研究的热点．引入有机试剂,特别是引入季铵碱,可合成许多新型分子筛［１－４］． Ｄａｖｉｓ等［５,６］报道了利用有机硅 ＴＢＡＳｉ（Ｎ－Ｔｒｉｍｅｔｈｏｘｙｓｉｌｙｌｐｒｏｐｙｌ－Ｎ,Ｎ,Ｎ－ｔｒｉ－ｎ－ｂｕｔｙｌａｍ－ｍｏｎｉｕｍ ｂｒｏｍｉｄｅ）, ＴＰＡＳｉ（Ｎ－Ｔｒｉｍｅｔｈｏｘｙｓｉｌｙｌｐｒｏｐｙｌ－Ｎ,Ｎ,Ｎ－ｔｒｉ－ｎ－ｐｒｏｐｙｌａｍｍｏｎｉｕｍ ｂｒｏｍｉｄｅ）为结构导向剂合成了 ＺＳＭ－５和 ＺＳＭ－１１．通过２９Ｓｉ ＮＭＲ研究证明有机硅进入了分子筛骨架…     

MCM－41中孔分子筛的合成及其性质

以十六烷基三甲基溴化铵（ＣＴＡＢ）作模板剂，研究了水热体系中中孔ＭＣＭ－４１分子筛的合成条件。在Ｈ_２Ｏ／Ｓｉ介于１２～１００，Ｓｉ／Ａｌ介于１０～∞，ＣＴＡＢ／Ｓｉ介于０．０８～０．２时，可以合成出ＭＣＭ－４１分子筛。在加入煤油等混合烃的合成体系中，可以合成出孔径大于４ｎｍ的ＭＣＭ－４１分子筛。用ＸＲＤ、ＳＥＭ、Ｎ_２吸附对合成样品加以表征，证明它们具有典型的中孔分子筛特性。探针反应证明它具有中强酸中心。     

Pt／H－Ga－Si杂原子分子筛催化剂上丙烷芳构化

考察了在具有Ｐｅｎｔａｓｉｌ孔道结构的Ｈ－Ｇａ－Ｓｉ与Ｐｔ／Ｈ－Ｇａ－Ｓｉ杂原子分子筛及ＨＺＳＭ－５分子筛催化剂上的丙烷芳构化。Ｐｔ／Ｈ－Ｇａ－Ｓｉ有较高催化活性和芳烃选择性，用ＸＲＤ、ＴＥＭ和ＴＰＲ等技术对催化剂进行了表征，讨论了Ｐｔ与Ｇａ的相互作用。Ｐｔ／Ｈ－Ｇａ－Ｓｉ为双功能催化剂，Ｐｔ促进烷烃脱氢成为烯烃，还能降低丙烷裂解活性，而且可稳定骨架Ｇａ，使其不易脱除；Ｇａ可以提高中间烯烃转变为芳烃的选择性。Ｈ－Ｇａ－Ｓｉ与ＨＺＳＭ－５上的丙烷芳构化机理不同。Ｈ－Ｇａ－Ｓｉ上为丙烷脱氢机理，Ｇａ脱去Ｈ＋形成活泼正碳离子，同时由于骨架Ｇａ与分子筛Ｂ酸位相邻，所以可提高芳烃选择性；ＨＺＳＭ－５上丙烷活化是经过裂化机理，再通过氢转移步骤形成芳烃。     

TS分子筛催化性能研究Ⅰ．TS－2分子筛催化1，2－丙二醇液相氧化反应的研究

ＴＳ分子筛催化性能研究Ⅰ．ＴＳ－２分子筛催化１，２－丙二醇液相氧化反应的研究①伏再辉尹笃林（湖南师范大学精细催化合成研究所，长沙４１００８１）关键词ＴＳ－２分子筛１，２－丙二醇氧化催化氧化自１９８３年Ｔａｒａｍａｓｓｏ［１］首次合成具有ＺＳＭ－５结构...     

ZSM—35分子筛的合成及模板效应的研究

以１，６－己二胺为模板剂合成了ＺＳＭ－３５分子筛，通过对比ＺＳＭ－３５、ＺＳＭ－５和丝光沸石的合成条件，采用化学组成分析、热重分析及＾１３ＣＮＭＲ等技术研究了１，６－己二胺的模板效应。结果表明，二者均对ＺＳＭ－３５有较好的模板作用，而１，６－己二胺对ＺＭＳ－５的模板效应更佳。     

CuY和Cu－ZSM－5催化剂上NO直接分解活性及活性中心的研究

研究了ＣｕＹ，Ｃｕ－ＺＳＭ－５分子筛制备条件对ＮＯ直接分解活性的影响．结果表明，在不同酸碱度下交换的ＣｕＹ分子筛，在ｐＨ＝９时活性较好，而Ｃｕ－ＺＳＭ－５型在ｐＨ＝７时较好．随交换度提高，Ｃｕ－ＺＳＭ－５活性上升，而ＣｕＹ交换度达４５％后活性趋于平稳：用ＤＴＡ，ＴＰＤ，ＸＰＳ及ＩＲ等技术，对活性中心进行了研究，表明钢是以水合离子形式与分子筛中Ｎａ＋进行交换．Ｃｕ－ＺＳＭ－５的活性位单一，ＣｕＹ上则有两种ＮＯ吸附位．经４００℃焙烧后，铜优先占据Ｙ的β笼，此即活性位．未经焙烧的样品中铜主要以Ｃｕ２＋存在．４００℃抽空处理产生Ｃｕ＋．讨论了ＮＯ在含铜样品表面的反应过程．     

ZSM－5沸石中V的还原性能

用ＴＰＲ并结合ＸＲＤ、ＥＳＲ和ＸＰＳ等测试手段研究了Ｖ（Ⅳ，Ⅴ）－ＺＳＭ－５、Ｖ２Ｏ５－／ＺＳＭ－５（分别用浸渍法和机械混合法制备）及Ｖ２Ｏ５样品的还原性能，获得了还原过程中物相及钒离子价态变化的信息，发现分散在分子筛表面上的Ｖ（Ⅴ）还原温度比Ｖ２Ｏ５低，而位于ＺＳＭ－５骨架上的Ｖ（Ⅴ）却比Ｖ２Ｏ５更难还原。高于１２００Ｋ骨架Ｖ才开始还原；高于１３７０Ｋ，Ｖ－ＺＳＭ－５分子筛开始解体并转变成方英石结构，从骨架中析出的Ｖ完全还原成低价态。     

硅改性ZSM－5沸石分子筛的酸性、孔径和择形催化性能的研究

在不同条件下用各种硅改性剂对ＺＳＭ－５沸石分子筛进行改性，并将其用于催化乙苯歧化生成对二乙苯的反应。实验结果表明，在合适条件下用ＳｉＣｌ＿４对ＺＳＭ－５改性后，可以获得高性能形选催化剂。硅改性可以有效地消除催化剂外表面酸中心，并能对分子筛孔道进行微调。根据反应结果和反应物在催化剂中的扩散系数判断，当改性后催化剂的孔道半径与ＮａＺＳＭ－Ｓ沸石孔道半径相近时，其催化选择性最佳。     

影响水热合成VPI-5及Si-VPI-5的因素

使用二正丙胺(DPA)和二正丁胺(DBA)作结构导向剂合成出VPI-5和Si-VPI-5,并以二异丙胺(DIPA)为结构导向剂成功地合成出高结晶度的超大孔磷酸铝分子筛VPI-5,其XRD谱图中未检测出其他杂质峰.VPI-5分子筛不同于一般中微孔磷酸铝分子筛,合成条件极其苛刻,为此对原料组成、成胶条件、陈化时间和温度、晶化时间和温度、结构导向剂种类、pH等合成条件对VPI-5分子筛结晶度的影响作了较为详尽的研究,结果表明有机胺在晶化过程中具有结构导向作用,但不起空间填充作用,加有机胺前的陈化过程是必要的.     

Synthesis and Characterization of the Large Pore Molecular Sieves VPI-5 and Si-VPI-5

The large pore molecular sieves VPI-5 and Si VPI-5 were synthesized by using three organic amines (dipropylamine, diisopropylamine and dipentylamine) as the structure-directing agents. Compared with general alumlnophosphate molecular sieves, the synthesis of the molecular sieves of VPI-5 type ls of many unique features. Both VPI-5 and Si-VPI-5 were characterized by XRD, IR, TG-DTA, and MAS-NMR.     

Synthesis of a positional scanning library of pentamers of N-alkylglycines assisted by microwave activation and validation via the identification of trypsin inhibitors

A positional scanning library of 625 N-alkylglycine pentamers has been synthesized on solid-phase, employing a set of 10 commercially available primary amines as a source of chemical diversity. The iterative synthetic steps were carried out in tea bags and accelerated by using microwave assisted organic synthesis (MAOS). The reactivity study of the primary amines used as diversity sources led to determine their relative reactivity values and equireactivity factors, which were applied to the library synthesis to ensure comparable concentrations of all final oligomers in the mixtures. This library was validated by the screening, deconvolution, and identification of trypsin inhibitors. These compounds are of potential interest for controlling the intracellular transport of TRPV1 channel.     

ZSM‐5 Zeolite Nanosheets with Improved Catalytic Activity Synthesized Using a New Class of Structure‐Directing Agents

A new series of multiquaternary ammonium structure‐directing agents, based on 1,4‐diazabicyclo[2.2.2]octane, was prepared. ZSM‐5 zeolites with nanosheet morphology (10 nm crystal thickness) were synthesized under hydrothermal conditions using multiquaternary ammonium surfactants as the zeolite structure‐generating agents. Both wide‐angle and small‐angle diffraction patterns were obtained using only a suitable structure‐directing agent under a specific zeolite synthesis composition. A mechanism of zeolite formation is proposed based on the results obtained from various physicochemical characterizations. ZSM‐5 materials were investigated in catalytic reactions requiring medium to strong acidity, which are important for the synthesis of a wide range of industrially important fine and specialty chemicals. The catalytic activity of ZSM‐5 materials was compared with that of the conventional ZSM‐5 and amorphous mesoporous aluminosilicate Al‐MCM‐41. The synthesis strategy of the present investigation using the new series of structure‐directing agents could be extended for the synthesis of other related zeolites or other porous materials in the future. Zeolite with a structural feature as small as the size of a unit cell (5–10 nm) with hierarchically ordered porous structure would be very promising for catalysis.     

Mild N-deacylation of secondary amides by alkylation with organocerium reagents

Secondary amides are a class of highly stable compounds serving as versatile starting materials, intermediates and directing groups (amido groups) in organic synthesis. The direct deacylation of secondary amides to release amines is an important transformation in organic synthesis. Here, we report a protocol for the deacylation of secondary amides and isolation of amines. The method is based on the activation of amides with Tf₂O, followed by addition of organocerium reagents, and acidic work-up. The reaction proceeded under mild conditions and afforded the corresponding amines, isolated as their hydrochloride salts, in good yields. In combination with the C-H activation functionalization methodology, the method is applicable to the functionalization of aniline as well as conversion of carboxylic derivatives to functionalized ketones.     

Multialkylation of aqueous ammonia with alcohols catalyzed by water-soluble Cp*Ir-ammine complexes

Novel water-soluble Cp*Ir-ammine complexes have been synthesized, and a new and highly atom-economical system for the synthesis of organic amines using aqueous ammonia as a nitrogen source has been developed. With a water-soluble and air-stable Cp*Ir-ammine catalyst, [Cp*Ir(NH(3))(3)][I](2), a variety of tertiary and secondary amines were synthesized by the multialkylation of aqueous ammonia with theoretical equivalents of primary and secondary alcohols. The catalyst could be recycled by a facile procedure maintaining high activity. A one-flask synthesis of quinolizidine starting with 1,5,9-nonanetriol was also demonstrated. This new catalytic system would provide a practical and environmentally benign methodology for the synthesis of various organic amines.     

Stereoselective and diversity-oriented synthesis of trisubstituted allylic alcohols and amines

Stereoselective and diversity-oriented synthesis of trisubstituted olefins was achieved by using ortho-diphenylphosphanyl benzoate (o-DPPB) as a directing group for allylic substitution. The starting point of this methodology was a set of α-methylene aldehydes derived from Baylis-Hillman adducts. Subsequent addition of different organometallic reagents led to a variety of allylic alcohol substrates. After introduction of the reagent-directing o-DPPB group, copper-mediated allylic substitution with a wide range of Grignard reagents enabled the stereoselective construction of a large number of E-configured trisubstituted allylic alcohols and amines in excellent yields and stereoselectivities. Remarkable is the synthetic flexibility, which allows a wide range of permutations starting from an aldehyde followed by successive introduction of the substituents R(2) and R(3) from organometallic Grignard based reagents. Thus, starting from only a few precursors, a diversity-oriented synthesis of stereodefined trisubstituted allylic alcohols and amines becomes possible.     

Rhodium(III)‐Catalyzed CH Activation and Indole Synthesis With Hydrazone as an Auto‐Formed and Auto‐Cleavable Directing Group

An efficient, practical, and external‐oxidant‐free indole synthesis from readily available aryl hydrazines was developed, by using hydrazone as a directing group for Rh^III‐catalyzed C?H activation and alkyne annulation. The hydrazone group was formed by in situ condensation of hydrazines and C?O source, whereas its N?N bond was served as an internal oxidant, for which we termed it as an auto‐formed and auto‐cleavable directing group (DG^auto). This method needs no step for pre‐installation and post‐cleavage of the directing group, making it a quite easily scalable approach to access unprotected indoles with high step economy. The DG^auto strategy was also applicable for isoquinoline synthesis. In addition, synthetic utilities of this chemistry for rapid assembly of π‐extended nitrogen‐doped polyheterocycles and bioactive molecules were demonstrated.     

Novel multicomponent reactions of primary amines and alkyl propiolates with alloxan derivatives in water

A water-accelerated multicomponent synthesis of organic target molecules has been used as a key method for the preparation of novel barbiturate derivatives. The three-component condensation reactions of primary amines with alkyl propiolates in the presence of alloxan derivatives in water are developed as efficient and clean green synthetic procedures for the high-yielding preparation of alkyl 2-(5-hydroxy-2,4,6-trioxohexahydro-5-pyrimidinyl)-3-(alkyl or arylamino)-2-propenoates. The above synthetic protocol provides rapid access to novel and diversely substituted barbiturate derivatives.     

Electrochemically promoted C-N bond formation from amines and CO2 in ionic liquid BMIm-BF4: Synthesis of carbamates

A new electrochemical procedure for the synthesis of organic carbamates from amines and carbon dioxide has been developed using selective cathodic reduction of carbon dioxide in CO2-saturated room-temperature ionic liquid BMIm-BF4 solutions containing amines 1a-j, followed by addition of EtI as an alkylating agent. The synthesis was carried out under mild (PCO2 = 1.0 atm, t = 55 degrees C) and safe conditions, and the use of volatile and toxic solvents and catalysts (according to the growing demand for ecofriendly synthetic methodologies), as well as of any supporting electrolyte (for a very easy workup of the reaction mixture), was avoided. Carbamates 2a-j were isolated in good to high yields.