双四唑肼的结构表征与合成工艺优化

化学工程师Chemical Engineer2021年第2期Sum305No.2科研与开发D0I：10.16247/ki.23—1171/tq.202102072-耕基-4-氯苯并廛哇类席夫碱的合成与表征*吴利欢，黄耀锋，陈丽雅,张华鑫，李湘(肇庆学院环境与化学工程学院，广东肇庆526060)摘要:以2—氨基-4—氯苯并噻唑为原料，以乙二醇为溶剂,在酸催化下与过量的水合肼缩合反应生成中间体(1)2—肼基-4—氯苯并噻唑，并探讨了合成中间体的最佳反应条件。

将中间体(1)分别与不同的醛或酮(2a~2d)反应，合成4种新型苯并噻唑类席夫碱(3a~3d),并对所合成的化合物进行了IRJH NMR、C NMR和MS结构的鉴定和表征。

关键词:2-肼基-4—氯苯并噻唑;席夫碱;合成;表征中图分类号:0626.2文献标识码:ASynthesis and characterization of the2-hydrazino-4-chlorobenzothiazole Shiff base derivatives*WU Li-huan,HUANG Yao-feng,CHEN Li-ya,ZHANG Hua-xin,LI Xiang(School of Environmental and Chemical Engineering,Zhaoqing University,Zhaoqing526060,China) Abstract:With glycol as solvent and acid catalysis,intermediate(1)2-hydrazino-4-chlorobenzothiazole was prepared by condensation of2-amino-4chlorobenzothiazole with excess hydrazine hydrate,and the optimal reaction conditions for the synthesis of intermediates was discussed.Four new4-chloro-2-hydrazinylbenzo[d]thiazole Shiff base(3a~3d)were synthesized by the reaction of different aldehydes or ketones(2a~2d)with intermediate(1),the structures of compounds3a~3d were identified and characterized by IR,1H NMR,13C NMR and MS techniques.Key words:2-hydrazino-4-chlorobenzothiazole;Shiff base;synthesis;characterization席夫碱因具有良好的杀菌性、抗病毒、抗肿瘤等生物活性而应用于医药领域⑴，此外，席夫碱还在催化［2］、荧光探针［3］和网络材料⑷等方面有广泛的应用。

1H-1, 2, 4-三唑合成工艺优化摘要：仅以甲酰胺、水合肼两种较为廉价的原料合成1H-1, 2, 4-三唑，研究了不同反应装置、摩尔比、反应温度、反应时间的影响及精制纯化溶剂的选择。

实验结果表明：当摩尔比1/3n（甲酰胺）：n（水合肼）=1：1.5，即甲酰胺与水合肼摩尔比为2：1，反应温度为185℃，反应时间为1.5h时，经乙酸乙酯洗涤精制后，产率可达82.35%，熔点与文献值吻合。

目标产物结构经红外光谱及元素分析确证。

关键词：1H-1, 2, 4-三唑；甲酰胺；水合肼；合成1H-1, 2, 4-三唑是重要的医药、农药、染料中间体。

尤其在医药领域，三唑药效团比咪唑具有更低的毒性并且呈现出多种生物活性, 如抗真菌、抗菌、抗结核、抗病毒等[1-3]。

1H-1, 2, 4-三唑及其衍生物已成为近几年来药物研究与开发的热点和重点领域之一[4-7]。

目前，合成1H-1, 2, 4-三唑主要有四种方法[8-9]：(1)由甲酰肼与甲酰胺反应制备，此法原料较贵，大多以过量的甲酰胺为溶剂，后处理需减压蒸除甲酰胺，操作非常复杂，若处理不好会大大降低产率；(2)由甲酸、水合肼、甲酰胺三种原料制备，此法选用原料较多，采用双管加料方式对加料速度要求严格，分两段反应，工艺较为复杂，生产周期较长；(3)先往甲酸中通入氨气，生成甲酸铵，再滴加水合肼，此法第一步通入氨气为两相反应，反应条件苛刻，反应时间长，操作较复杂；(4)由甲酰胺及水合肼制备，此法简单方便，产率较高，但据文献[10]报道反应时间较长为4.5-5h，且需过夜静置等待结晶析出，生产周期较长。

由于1H-1, 2, 4-三唑的价格直接影响三唑类产品的生产与应用，因此，进一步研究1H-1, 2, 4-三唑的合成工艺，通过改善反应条件缩短生产周期，提高产率，降低成本对工业生产有着现实意义。

本文对仅以甲酰胺、水合肼两种原料合成1H-1, 2, 4-三唑的工艺进行了进一步研究。

叠氮和重氮类新型高氮含能配合物的制备、表征及性能研究目前，世界上弹药小雷管用起爆药只有叠氮化铅（LA），其缺点是对机械刺激敏感，火焰和针刺感度低，在无约束条件下也能实现爆轰、危险性高、且有毒重金属铅含量高达71.14%。

工业雷管用起爆药品种也少，主要是二硝基重氮酚（DDNP）、高氯酸碳酰肼合锌（GTX）和硝酸肼镍（NHN）等。

为研究使用性能更优、安全性更好的新型起爆药，参考当前环境友好起爆药新目标，选择高能、钝感、含能配合物的发展方向，系统地研究40余种叠氮类和重氮类含能配合物的制备方法、晶体结构、热分析、非等温动力学、燃烧热、感度性能和应用性能，为新型起爆药的发展和应用提供基础数据。

本文的主要研究内容如下：（1）设计理念含能配合物的高氮含量和高能、低感度是一对矛盾体。

为合理地解决这对矛盾，本文设计的新型叠氮类含能配合物的通式为[M(L1)x(N3)2]n，根据叠氮根配位的多样性，可以形成单核、多核、1D链状或2D平面结构的叠氮含能配合物；重氮类含能配合物的通式为[M(L2)x](ClO4)2，选用具有双配齿的含能配体L2，可以形成具有微孔的3D MOFs结构，这将是含能配合物的发展方向之一。

其中：金属离子M选用对含能配合物的分解过程具有明显的催化作用的锰、钴、镍、铜、锌、镉和铅等金属元素。

含能配体L的高氮含量和高能、低感度同样是一对矛盾体，因此，综合考虑L的结构和氮含量从低到高的设计思路，系统地研究确定10种直链类高氮化合物（N%=37.00~47.00%）或唑类杂环高氮化合物（N%=40.00~84.00%）。

通过Gaussian03理论研究高氮含能配体L的最高占据分子轨道（HOMO）和最低未占据分子轨道（LUMO）结构，理论预测含能配体L的配位原子，预测含能配合物的结构。

（2）含能配合物的制备和晶体结构表征应用实验方法制备出了9个系列共39种叠氮含能配合物和1个系列共5种重氮类含能配合物，其中42种含能配合物是首次制备的新型含能配合物。

多齿鳌合配体双四唑胺合成方法的改进摘要用水热法合成并提纯双四唑胺,优化了传统合成方法并使实验步骤缩减,使产率和纯度有较大提高。

关键词双四唑胺水热法合成多齿鳌合配体由于三唑、四唑及其衍生物的多功能性质和广泛的应用前景,科学家们对该类化合物的生成原理、合成方法以及它们的结构和应用研究只增不衰[1~3]。

在材料能源科学领域,三唑、四唑类化合物含氮量高且具有高的正生成焓,是高密度能量材料,被用于制作高能、低烟、无毒钝感炸药;在药学领域,三唑、四唑类化合物是重要的中间体,被用于合成各种含唑衍生物;在无机-有机杂化的多功能材料领域,它们也常被用来桥联过渡和稀土金属离子,构筑各种结构新颖、性能优良的功能配合物[4~6]。

双四唑胺(H 2BTA)是一个含有9个配位氮原子的多齿鳌合杂环配体,具有很强的配位能力,理论上该配体存在几百种不同的配位方式。

图1是双四唑胺在不同的pH条件下的4种存在形式,各种形式都有不同配合物报道,其中HBTA -和BTA 2- 2种阴离子配体与金属离子的配合物比较多见。

图2是双四唑胺几种常见的配位方式。

早在1963年,William P. Norris等就报道了双四唑胺的2种传统的合成方法:一种是以叠氮化钠和二氰胺钠为原料,HCl为催化剂,回流法合成;另一种是以5 氨基四唑,溴化氰和叠氮化钠为原料,HCl为催化剂,先低温搅拌后高温回流合成。

但随后的几十年间,双四唑胺一直未受到科学家们的关注[7]。

2005年,Thomas等研究了双四唑胺合铜配合物的晶体结构和磁性,并指出该类配合物具有作为含能材料的应用前景[8]。

2007年,GuoYong等人通过H 2BTA分别与三氨基胍硝酸盐、硝酸胍、5 氨基四唑等在一定条件下反应,得到一系列相应的双四唑胺盐,并研究了它们的生成热、爆炸性质和热稳定性等性质,发现它们是高能量、环境友好型含能材料[9]。

2007年到现在,笔者成功合成并报道了一系列双四唑胺配体构筑的过渡和稀土金属配合物,并研究了部分化合物的光、磁性质[10]。

两个四唑配合物的原位合成、多样化配位模式和强荧光性质高继兴;徐庆;谭育慧;刘艺;温和瑞;唐云志【摘要】在路易斯酸ZnCl2或MnSO4·7H2O作用下,通过1-甲基-1-氢-咪唑-4,5-二甲腈与NaN3水热原位合成了2个四唑配合物:{[Zn2(midt)(Hmidt)](N3)·H2O}n(1)和[Mn(midt)2·(H2O)2]· H2O(2)(midt=1-甲基-1-氢-咪唑-4,5-二四唑).X射线单晶衍射表明尽管配合物1和2均结晶于同样的P(1)空间群,但他们有完全不同的结构.配合物1为一个有趣的二维聚合物结构,含有两个不同配位环境的锌原子和多种配位模式的midt配体,而配合物2为一个三维超分子结构,包含一个有趣的水分子链结构.固态下1和2分别在353和382 nm处显示出较强的蓝色荧光.【期刊名称】《无机化学学报》【年(卷),期】2016(032)007【总页数】8页(P1267-1274)【关键词】Sharpless反应;荧光;四唑配合物;晶体结构【作者】高继兴;徐庆;谭育慧;刘艺;温和瑞;唐云志【作者单位】江西理工大学工程研究院,赣州341000;江西理工大学工程研究院,赣州341000;江西理工大学工程研究院,赣州341000;江西理工大学工程研究院,赣州341000;江西理工大学工程研究院,赣州341000;江西理工大学工程研究院,赣州341000【正文语种】中文【中图分类】O614.24+1;O614.7+11The tetrazole functional group has found a wide range of applications in medicinal chemistry as metabolically stable surrogates for a carboxylic acid groups,and in materials science as high densityenergymaterials[1].Especially,tetrazoles have attracted increasing attention in coordination chemistry due to the excellent coordination ability of four nitrogen atoms from the functional group to act as either a multidentate or a bridging building block[2-8].It has inspired that some new progress were made on the in situ synthesis of cycloaddition reactions recently.Our groups discovered the first pair of enantiomers ofmetal tetrazole complex([Cu(Tzmp)]n) from insitu[2+3]cycloaddition reactions of a flexible organic nitrile ligand with sodium azide in the presence of Cu2+as Lewis acid[9].Following from that,we obtained another new pair enantiomers[Mn(4-tzba)(bpy)2·H2O](bpy)·3H2O(4-tzba=4-tetrazolbenzoic acid)from[2+3]cycloaddition reaction ofbpy,4-tzba,sodium azide and manganese acetate[10].These investigations have suggested that different conditions such as different Lewis acids(metal cations),negative ions, temperaturesand pH valueshavea significantinfluence on their coordination modes of tetrazolyl groups and crystal structures[11-15].In our previous work,most reaction substitutes of the in situ metal tetrazole complexes are organic mononitrile[16-19],the metal tetrazole complexes obtained from the in situ syntheses of bisnitriles and multinitriles are relatively spare[20-21]. When the organic bisnitriles were used assubstitute in[2+3]cycloaddition reactions,there are possible two tetrazolyl groups formed from in situ produced ligands, thus,they maybe exhibit diversified coordination modes and form variable structures.As an ongoing effect to explore new type of bistetrazole complexes and analyze the crystal structures and photluminescent properties,we have attempted to construct two new tetrazole complexes,{[Zn2(midt)(Hmidt)](N3)·H2O}n(1)and[Mn(midt)2· (H2O)2]·H2O(2),by using 1-methyl-1H-imidazole-4,5-dicarbonitrile(midn)assubstitute in Sharpless reaction. To our surprise,1 contains four different types of tetrazolyl groups in terms of their coordination modes. Here we detailed their crystal structures,photoluminescent properties and PXRD.1.1 SynthesisAll reagents were purchased from commercial sources and used as received.As shown in Scheme 1, hydrothermal reaction ofmidn(0.026 4 g,0.2 mmol), NaN3(0.039 0 g,0.6mmol)(Caution:Metalazidesmay be explosive),and ZnCl2(0.027 2 g,0.2 mmol)or MnSO4·7H2O(0.055 4g,0.2mmol)in amixed solution of ethanol(0.5 mL)and water(2 mL)for 3 days give colorless block crystals of 1 or yellow block crystals of 2.For1,Yield:0.031 1 g,49.8%based on mind. Anal.Calcd.forC12H11Cl0N23OZn2(%):C,23.09;H, 1.78;N,51.61.Found(%):C,23.12;H,1.75;N, 51.58.IR(KBr,cm-1):3 483(m),3 201(m),2 095(s), 1 648(s),1 583(m),1 492(s),1 449(m),1 380(s),1 278 (w),867(m),760(m),680(m).For 2,Yield:0.035 0 g, 62.3%.Anal.Calcd.for C12H18N20O4Mn(%):C,25.68;H,3.23;N,49.90.Found(%):C,25.71;H,3.19;N, 49.85.IR(KBr,cm-1):3 481(m),3200(m),1 652(s), 1 582(m),1 488(s),1 439(m),1 380(s),1 250(s),967 (m),762(m),680(m).1.2 CrystallographyX-ray single-crystal diffraction data for 1 and 2 were collected on a Bruker P4 diffractometer with Mo Kαradiation(λ=0.071 073 nm)at296K using the θ-2θscan technique and corrected by Lorentz-polarization and absorption corrections[22-23].Both crystal structures were solved by direct method and refined by the full-matrixmethod based on F2bymeans of the SHELXLTL software package[24].Non-H atoms were refined anisotropicallyusingall reflectionswith I＞2σ(I). All H atomswere generated geometrically and refined using a“riding”model withUiso=1.2Ueq(C).The asymmetric units and the packing views were drawn with DIAMOND(Brandenburg and Putz,2005).Angles between some planeswere calculated using DIAMOND, and other calculations were carried out using SHELXLTL.Crystal data and structures refinement for1 and 2 are listed in Table1.CCDC:1451129,1;1451130,2.1.3 Physical techniquesPL emission spectra were measured at room temperature using a spectra fluorophotometer(JASCO, FP-6500)with a xenon lamp(150W)asa lightsource. Powder X-ray diffraction(PXRD)data were recorded on a Rigaku D/MAX 2000 PC X-ray diffraction instrumentwith CuKαradiation(λα1=0.015 405 98 nm,λα2=0.015 444 26 nm)under the generator voltage of 40 kV and tube current of 40 mA,by using continuousscan type from 5.0°to 80.0°at room temperature.2.1 Synthesis and crystal structures of complexes 1 and 2Compared by IR spectra of complex 1 andmidn,a serial of new strong peaks ranges from 1 652 to 1 439 cm-1appear while the absorption of cyano group at 2 355 cm-1νas(C≡N)andνs(C≡N)disappear in 1 and2,indicating that the[2+3]Sharpless reaction between cyano groups and azide anions have finished[16-19]. Especially,a sharp peak at 2 095 cm-1existing in 1 without in 2 suggest that there are possible azide anions in complex 1.Single crystal X-ray diffraction analyses reveal that1 belongs to triclinic crystal system with P1 space group.The fundamental building unit of 1 consists of two crystallgraphi cally Zn(Ⅱ)ions,one midt ligand, one protonated Hmidt ligands(one of the tetrazole groups is protonated),one N3-anions,and one H2O molecule.As depicted in Fig.1,Zn1 and Zn2 have totally different coordinated environment.Zn1 adopts a slightly distorted hexa-coordinated octahedral geometry in which twoβN atoms(N11 andN14ii) from different tetrazolyl groups occupy the axial vertexposition with an angle of 175.01(10)°(N(14)ii-Zn(1)-N(11)),while the basic planar is constituted by four N atoms(N1,N10,N9iand N20)from two chelating midt ligands via theαN atoms of tetrazolyl group and exposed N atoms of imidazole ring.Zn2 has a distorted tetrahedral geometry which connects four independent αN(N16,N17,N6iiiand N7iii)atoms from different tetrazolyl groups.Interestingly,we can clearly discover that all the Zn1-N distances(ranging from 0.211 1(2) to 0.222 4(2)nm)are obviously longerthan those of Zn2-N distances(0.197 5(2)～0.199 0(2)nm).As can be seen in Fig.2a,there also exist two crystallgraphically different midt ligands in 1.One midt ligand(named as midt1)acts as a 3-connected bridging spacer through N17,N16,N14,N11 and N20 linking three different zinc atoms such as Zn1,Zn2 and Zn1viii,while the otherone(correspondingly called as midt2)acts as a 3-connected bridging spacer via N1,N10,N9,N7 and N6 connecting the other three zinc atoms such as Zn1,Zn1viand Zn2vii.Remarkably, we can clearly observe that the plane of midt1 is nearly perpendicular to that of midt2,the dihedral angle between them is 89.14°calculated by dia mond software.As shown in Fig.2b,firstly all the midt1 ligands link different zinc atoms with“end to end”modes to produce an infinite linear structure along the a axis;meanwhile,all themidt2 ligands connect the other zinc atoms to form another linear structure along the c axis,then they cross-link to extend to a 2D sheet which parallel to the ac plane;lastly the neighboring 2D sheets are further packed by the strong supramolecular interactions such as intermolecular hydrogen bonds,π-πstacking of tetrazolyl rings and O-H…πinteractions,which extend the structure into a 3D network.It should be emphasized that there exist four totally different coordination modes of tetrazolyl groups inmidt1 and midt2 ligands.In midt1 (Fig.2a,left),one tetrazolyl group adoptsμ3coordination mode and the otherusesμ1coordination mode by one ofαN atoms.In midt2(Fig.2a,right),both tetrazolyl groups adoptμ2coordination mode,but one of them uses twoαN atoms of tetrazolyl ring and the other employs oneαN atom and oneβNatom of tetrazolyl ring.According to the summary oncoordinationmodesof tetrazolylgroupsby Xiong etal[1], the above coordination modes belong to modeⅦ, modeⅠ,modeⅢand modeⅤrespectively.To our knowledge,few literatures reported that so many coordination modes of tetrazolyl groups are coexistent in the same complex before.Although 2 also crystallizes in P1 space group,it has completely different structure from 1.The asymmetric unit of 2 is composed of halfMn(Ⅱ)cation and halfmidt ligand,one coordinated watermolecule and one lattice water molecule.As shown in Fig.3a, the coordination geometry around Mn(Ⅱ)center can be viewed as a slightly distorted octahedron which is surrounded by two coordinated water molecules and four N atoms of two chelating midt ligands.To our surprise,only half of the tetrazolyl groups in midt ligands of 2 participate in coordination.Because of the steric hindrance effect of the uncoordinated tetrazolyl groups,it prevent forming an infinite high dimensionalmetal organic framework.Nevertheless,it become an important factor to assembly themolecules into a three dimensional supramolecular structure, since there exist a lot of strong intermolecular hydrogen bonds between the uncoordinated tetrazolyl groups and watermolecules such as O(2W)-H(2WA)…N(5)iv(0.282 1(3)nm)and O(1W)-H(1WB)…N(4)v(0.280 8(3)nm).In additional,other interesting supramolecular interactions includingπ-πstacking interac-tionsbetween the neighboring tetrazolyl planes(0.345 4 nm)and imidazolyl planes(0.345 4 nm)also contribute to stabling the whole structure(Fig.3b).One of themost striking features is that there lies a one dimensionalwater cluster in 2.As shown in Fig. 4,the basic building block can be regarded as a tetrameric water cluster which is constituted by two equivalents coordinated watermolecules(O1Wvi,O1W) and two equivalents lattice water molecules(O2Wvi, O2W).The short contacts and the reasonable angles between them indicate the existence of strong hydrogenbonds(Table2),which favors the construction of a tetrameric water cluster.Then,these building blocks are further extended by strong intermolecular hydrogen bonds between lattice water molecules(O(2W)-H(2WB)…O(2W)v0.287 0(5)nm),resulting in the formation of an infinite one dimensionalwater chain.2.2 Fluorescence properties and powder X-ray diffraction analysisWe studied the solid-state luminescent emissionspectra of 1 and 2 at room temperature(Fig.5). Complex 1 display a very strong emission at353.4 nm. In comparison with 1,complex 2 appears a distinct“Einstein”shift,the maximum emissive peak occurs at382.0 nm,meanwhile the relative intensity decreases. According to previous research and our investigation on tetrazolate complexes,the emission peak ranging from 350 to 380 nm is attributed to the ligand to ligand change transition[11-19],since the luminescent emission from d-d charge transition of Zn(Ⅱ)andMn(Ⅱ)mainly occurs in 450 and 650 nm respectively.Besides, in comparison with 2 the significant improvement of 1 at intensity is tentatively attributed to the weak Zn…Zn(3d-4s)with d10cluster-centered(CC)excited states. 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