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1.
以廉价易得的1-硝基-3-甲氧基甲苯为原料,依次经硝基还原、保护氨基、硝化、保护氨基后还原硝基、氨基甲基化,再与异硫氰酸酯环化构建2-氨基苯并咪唑环、脱去羟基保护基、成醚、硝基还原和乙酰化反应,合成JAK2II型抑制剂CHZ868,总收率6.24%,其结构经1H NMR, 13C NMR和LC-MS确证。  相似文献   

2.
胡昆  谢宇轩  任杰 《合成化学》2021,29(4):308-314
以4-哌啶甲酸为原料,经酯化、烷基化、酯水解、酰化、脱水和还原反应合成中间体N-苄基-4-哌啶甲醛8;再以3,4-二甲氧基苯甲醛为原料,经缩合、还原、分子内环化反应合成中间体5,6-二甲氧基-1-茚酮9;最后中间体8和中间体9经缩合、还原反应后成盐合成了抗阿尔茨海默病药物盐酸多奈哌齐,总收率56.8%,其结构经1H NMR和13C NMR确证。该路线具有原料廉价易得、操作简便、反应条件温和、后处理简便、收率较好等优点。   相似文献   

3.
夏然  孙莉萍  杨西宁  渠桂荣 《应用化学》2015,32(12):1398-1401
提出了合成2,6-二氯嘌呤核苷和2-氯腺苷的新方法。 以商品化的2,6-二氯嘌呤和四乙酰核糖为原料,在5%(摩尔分数)三氟甲磺酸催化下,得到缩合物2',3',5'-三-O-乙酰基-2,6-二氯嘌呤核苷。 缩合物在浓H2SO4催化下,以89%的收率得到2,6-二氯嘌呤核苷;在NH3/CH3OH体系中氨解和脱除乙酰基,以92%的收率得到2-氯腺苷。 反应规模可以扩大到100 g,收率未降低。 该方法原料价格低廉,避免使用重金属催化剂,操作简便,中间体及产物可以通过结晶的方法纯化得到,显示出潜在的应用价值。  相似文献   

4.
以3-(2-氯嘧啶-4-基)-1-甲基吲哚和4-氟-2-甲氧基-5-硝基苯胺为起始原料,经缩合、取代、还原、酰化及成盐反应合成了抗肿瘤药物--甲磺酸迈瑞替尼,总收率66.2%,其结构经1 H NMR, IR 和MS确证。  相似文献   

5.
以廉价易得的取代酸为原料,经取代、硝基还原、氨基磺酰化、炔基格氏试剂加成和羰基化环化反应合成了13个5-炔基噁唑啉-2-酮类化合物,收率为10.6%~71.8%。产物结构经1H NMR和13C NMR确证。   相似文献   

6.
李旻玥  宋荣聪  任杰  胡昆 《合成化学》2021,29(12):1077-1082
以3,4-二甲氧基苯乙酸为原料,经酰化、脱水、C-烷烃化反应、得到关键中间体α-异丙基-3,4-二甲氧基苯乙腈(5);再以3,4-二甲氧基苯乙酸为原料,经酰化、还原、N-烷烃化反应得到N-(γ-氯丙基)-N-甲基-3,4-二甲氧基苯乙胺(2); 2与5经过缩合得到了最终产物维拉帕米,总收率为25.4%,其结构经1H NMR和13C NMR确证。该合成路线具有原料廉价易得、操作简便、反应条件温和、后处理简便、收率较好等优点,具有较高的工业化前景。   相似文献   

7.
郇伟伟  程超  刘力  李蕾  李洁 《合成化学》2018,26(10):783-786
以2-氯-5-硝基吡啶为起始原料,经氢化、偶联和酰胺缩合反应合成Sonidegib,总收率71.4%,其结构经1H NMR和MS(ESI)确证。  相似文献   

8.
唐裕才  王萍  冉书童  陈飘 《应用化学》2019,36(6):664-670
发展了一种硝基烯烃与磺酰肼脱硝磺酰化反应合成(E)-β-烯基砜。 以四丁基碘化铵(TBAI)/过硫酸钾(K2S2O8)为催化氧化体系,多种硝基苯乙烯衍生物与取代磺酰肼发生自由基加成/脱硝基反应,以中等到良好的收率获得各种(E)-β-烯基砜。 反应具有底物适用范围广、反应操作简单、无金属催化及中性反应条件等优点,为含β-烯基砜类化合物的合成提供了一条高效、简单、环境友好的新途径。  相似文献   

9.
氯法拉滨是临床上唯一可以特异性地治疗儿童白血病的药物,2004年被美国食品和药物管理局批准上市.由于现有合成方法存在路线长、收率低和α/β异构体难以分离等问题,限制了该药物的广泛使用和进一步研究.以廉价且商品化的2-氯腺苷为原料,通过乙酸酐保护糖环上的3个羟基,在水合肼和乙酸作用下,选择性地脱除2'位的乙酰基.然后,以商品化的氟代试剂二乙胺基三氟化硫(DAST)进行2'位羟基的氟代反应,再使用NH3/MeOH饱和溶液脱除乙酰基可得氯法拉宾.这4步反应的总收率为49%,且得到的产品全部为β构型.同时,还发现2位取代基的位阻越大,越有利于选择性脱除2'位的乙酰基.本方法可以在克级规模上进行生产,收率无下降,同时中间体及产物的纯化不需要通过柱层析分离,显示出良好的应用前景?.  相似文献   

10.
宋方方  赵岗  光善仪  徐洪耀 《合成化学》2018,26(11):833-835
以罗丹明B为起始原料,首先与乙二胺经闭环反应制得中间体罗丹明B乙二胺(1),在K2CO3作用下与三聚氯嗪经亲核取代反应制得罗丹明B乙二胺-三聚氯嗪化合物(2),收率75.8%; 2与亚氨基二乙酸在K2CO3作用下,经氮气保护进一步发生亲核取代反应合成了一种新型罗丹明基衍生物分子--罗丹明B乙二胺-三聚氯嗪-亚氨基二乙酸,收率63.3%,三步总收率45.5%,其结构经1H NMR、 13C NMR、 IR和HR-MS(ESI)表征。  相似文献   

11.
Arenediazonium tetrafluoroborates (ArN2BF4 where Ar = X-C6H4; X = H, 2-Me, 3-Me, 4-Me, 4-MeO, 4-MeCO, 4-EtOCO, 2-Ph, 2-Cl, 3-Cl, 4-Cl, 4-Br, 4-I, 3-NO2 and 4-NO2) were easily converted to aromatic aldehydes (ArCHO) in good yields through the palladium-catalyzed reaction with CO and Et3SiH or polymethylhydrosiloxane (PMHS) at room temperature.  相似文献   

12.
报道了配合物Ln(X-P)3·3H2O[其中X=H,2-Cl,4-Br,3-OH,3-NO2,2-OCH3,2-CH3,2,4-二氯,P=2-(COO)C6H4CONHC6H5-nXn,n=1,2;Ln=Pr(Ⅲ),Nd(Ⅲ)]的制备,并用元素分析、红外光谱、电子反射光谱、热重分析进行了表征。结果表明,配位是通过羧酸羟基氧原子和酰胺羰基氧原子进行的,含3分子配位水。通过电子反射光谱数据,对Slater-Condon参量(Fk)、Lande参量(ξ4f)、Nephelauxit比率(β),平均共价参数(δ)、平均成键参数(b1/2)、F4/F2、F6/F2比值进行了计算,对配合物的共价成键情况进行了讨论。  相似文献   

13.
Arenediazonium tetrafluoroborates (ArN2BF4 where Ar=Ph, 4-MeC6H4, 4-BrC6H4, 4-IC6H4 and 4-NO2C6H4) reacted easily with CH2=CHSiMe3 at 25 δC to give ArCH=CH2, (E-ArCH=CHSiMe3 and Ar(Me3Si)C=CH2 in excellent yields under palladium(O) catalysis. (E)-ArCH=CHSiMe3 compounds were obtained predominantly and isolated in good yields by using an excess of CH2=CHSiMe3 over ArN2BF4. Protodesilylation of the reaction mixture afforded styrene derivatives.  相似文献   

14.
One series of 4-n-octyl-N-(4-X-benzylidene)anilines and two series of polar orthopalladated complexes derived from these of type Pd2(μ-Y)2 p-X-C6H3-CH = N-C6H4-C8H172; X: -H, -F, -Cl, -Br, -NO2, -CN, -CH3, -OCH3, -CF3, -COOCH3, -OCOCH3 and -OCOQH5; Y: -OAc and -Cl; have been synthesized and their mesogenic properties studied. In the polar Schiff bases used as organic ligands, the polar end group determines both the presence of the mesophase and the type of mesophase exhibited. In the complexes, however, it is the central structure of the molecule that practically always determines mesogenic behaviour. No acetato-bridged complex is mesogenic. All the chloro-bridged complexes, however, show mesogenic behaviour. All these compounds show smectic A mesophases with the exception of the CN compound, which only exhibits a nematic mesophase.  相似文献   

15.
A facile preparation of nitrogen-doped β-TiO2(N-doped β-TiO2) nanobelts and their visible-light photocatalytic activity were reported. The preparation of N-doped β-TiO2 nanobelts consisted of cation-exchange between layered sodium titanate nanobelts and NH4+ in aqueous solution at room temperature and subsequent calcination in air. Such a calcination treatment is beneficial to the formation of monoclinic N-doped β-TiO2 nanobelts. Various measurement results indicate that not only were the nitrogen atoms doped into the lattice of β-TiO2 nanobelts resulting in a strong visible-light absorption, but also a large number of defects were caused by them in the lattice, increasing the stability of β-TiO2. The photocatalysis enhancement of N-doped β-TiO2 nanobelts for the photodegradation of Rhodamine B was demonstrated.  相似文献   

16.
The substitution reactions of XC6H4COCl [X=2-, 3-, or 4-CH3; 2-, 3-, or 4-CH3O; 2-, or 4-I; or 2-, 3-, or 4-NO2] and YC6H4COONa [Y=2-, 3-, or 4-CH3; 2-, 3-, or 4-CH3O; 2-I; 4-NO2; or H] in a two-phase H2O/CH2Cl2 medium using pyridine-1-oxide (PNO) as an inverse phase transfer catalyst were investigated. In general, the kinetics of the reaction follows a pseudo-first-order rate law, with the observed rate constant being a linear function of the concentration of PNO in the water phase. In contrast to other analogous reactions, the hydrolysis reaction of 2-, 3-, or 4-NO2C6H4COCl in H2O/CH2Cl2 medium is catalyzed considerably by PNO and reaches an equilibrium. In the PNO-catalyzed reaction of XC6H4COCl and XC6H4COONa in H2O/CH2Cl2 medium, the order of reactivities of XC6H4COCl toward reaction with PNO in CH2Cl2 is 2-IC6H4COCl>4-IC6H4COCl>(C6H5COCl,3-CH3OC6H4COCl)>3-CH3C6H4COCl>(2-CH3C6H4COCl,4-CH3C6H4COCl)>4-CH3OC6H4COCl>2-CH3OC6H4COCl. Combined with the results of other analogous reactions, good Hammett correlations with positive reaction constant were obtained for the meta- and para-substituents, which supports that the XC6H4COCl–PNO reaction in CH2Cl2 is a nucleophilic substitution reaction.  相似文献   

17.
用紫外可见光谱法,在DMSO中测量了氯合间取代四苯基铁卟啉与多种咪唑类配体反应的平衡常数,研究了卟啉环上取代基、反应温度以及配体等因素对反应平衡常数的影响。利用温度系数法测定了反应体系的热力学函数ΔrHm和ΔrSm。  相似文献   

18.
用丁烷代替苯为原料生产马来酸酐 ,是低碳烷烃选择氧化成功实现工业化的极少数例子之一 [1] ,其中 VPO复氧化物是唯一能高活性且高选择性地催化这一过程的催化剂 .因而 ,这一领域的研究备受关注 [2 ,3] .以 VPO铵盐单晶结构的研究为例 ,迄今已对α- NH4 V ( HPO4 ) [4 ] ,β- NH4 V ( HPO4 ) [5] ,NH4 VOPO4 [6 ] ,NH4 VOPO4 · H2 O[7] 和 α- NH4 VO2 HPO4 [8] 等进行了结构研究 .作为催化剂活性物质( VO) 2 P2 O7的前驱体 ,β- NH4 ( VO2 ) ( HPO4 )也曾被 Pulvin等 [9,10 ] 由粉末衍射数据推测分子组成为NH4 ( VO…  相似文献   

19.
为了探究催化剂的结构和催化活性的关系,采用水热法制备了四种不同晶体结构的MnO2纳米催化剂(α-MnO2、β-MnO2、γ-MnO2和δ-MnO2),并考察了其低温NH3-SCR活性。结果表明,不同晶体结构催化剂的活性不同,依次为γ-MnO2 > α-MnO2 > β-MnO2 > δ-MnO2,γ-MnO2表现出最高的催化活性,NOx转化率在150-260℃超过90%。随后,通过X射线衍射(XRD)、扫描电子显微镜(SEM)、N2吸附-脱附、热重(TG)、红外光谱(FT-IR)、程序升温还原(H2-TPR)及吡啶吸附红外光谱(Py-FTIR)等表征手段对催化剂的结构和性质进行分析。结果表明,α-MnO2和β-MnO2为纳米棒,γ-MnO2和δ-MnO2为纳米针,催化剂的比表面积并不是影响低温NH3-SCR活性的主导因素。γ-MnO2具有适宜的孔道结构、较强的氧化还原能力、丰富的化学氧含量和Lewis酸酸性位点,是其具有最高低温NH3-SCR活性的原因。  相似文献   

20.
Differential scanning calorimetry (DSC), dilatometric and dielectric measurements have been used to study the phase transitions in [C(NH2)3]3BiBr6. The [C(NH2)3]3BiBr6 crystal undergoes four phase transitions: at 419, 429, 475 and 495 K (on heating). The high-temperature phase transition is clearly of first-order type and its high entropy effect allows classifying it as of the order–disorder type. X-ray diffraction studies showed that [C(NH2)3]3BiBr6 crystallises in monoclinic, centrosymmetric space group, C2/c. The anionic sublattice is composed of isolated BiBr63− octahedra. The infrared between 100 and 350 K and Raman spectra at room temperature in the frequency range related to the internal vibrations of guanidinium cations were studied for [C(NH2)3]3BiBr6, [C(NH2)3]3Bi2Br9, [C(NH2)3]3BiCl6xCl2 and C(NH2)3Cl to analyse the dynamical state of cations. At room temperature, the cations in the studied guanidinium halogenobismuthates(III) are almost rigid, so the mechanism of high-temperature phase transitions is probably connected with the release of rotation of the cations.  相似文献   

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