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1.
三羟甲基烷烃是用于醇酸树脂、聚氨酯树脂、表面活性剂、合成润滑油等的原料[1-3].三羟甲基十一烷(化学结构见图1)作为三羟甲基烷烃中直碳链最长的一员,不仅具有亲水性(分子中含三个亲水基),而且具有疏水性(含一个长直碳链亲油基),因此可用作表面活性剂.不仅如此,与同样用作乳化剂的一般高级脂肪醇(如十六烷醇)相比,可以在化妆品用的乳液中加入三羟甲基十一烷作乳化剂,以降低乳液的黏度,防止乳液中由于大量加入高级脂肪醇而导致产品黏度过高以至不能在皮肤上被充分涂抹开的状况发生[4].为制备智能芳香缓释型聚氨酯微胶囊壳材[5],需要设计聚氨酯的分子结构中含有能与相变石腊和油溶性香料有良好相容性的疏水链(三羟甲基十一烷与六亚甲基二异氰酸酯的加成物).因此,本文合成并表征了三羟甲基十一烷.  相似文献   

2.
多元醇及其二元混合物固-固相变的IR研究   总被引:9,自引:1,他引:8  
固固相变储能物质多元醇类以其有适宜的转变温度、较高的转变焓、具有经济和技术潜力而受到人们的重视,已在热力学和动力学等方面对其进行广泛和深入的研究[1-3],并通过红外光谱法研究了几种纯多元醇固固转变的机理[1].本文对几种多元醇及其二元混合物进行变温红外光谱的测定,进一步探讨了变化的规律.1 实 验11 药品:新戊二醇(NPG)为保证试剂(日本东京化成株式工业会社),三羟甲基乙烷(PG)超纯(日本东京化成株式工业会社),季戊四醇(PE)化学纯(北京化学试剂公司).12 仪器美国PE公司M1730型富里叶变换红外光谱仪;日本E012A号H…  相似文献   

3.
5-羟甲基噻唑合成工艺的改进   总被引:1,自引:0,他引:1  
5-羟甲基噻唑是一种重要的农药、医药中间体,可用于合成第二代抗AIDS药物利托那韦(Ritonavir)[1-3].Leanna M R等[4]和Gregory F H等[5]分别报道了2-氯-5-氯甲基噻唑经甲酸钠酯化、水解和催化氢化脱氯得到5-羟甲基噻唑的工艺,该工艺在酯化时需要使用有机溶剂和相转移催化剂,后处理麻烦;反应中存在较多副反应,需要活性炭脱色,成本较高.  相似文献   

4.
石阿鹏  饶子昆  郝建原 《合成化学》2020,28(11):949-954
分别以三羟甲基乙烷和辛二酸二乙酯为反应单体,通过酶催化的方式,得到了窄分的树枝状3元醇聚酯。通过1H-NMR, 13C-NMR以及GPC测试表征,我们对比了三羟甲基乙烷聚酯与丙三醇聚酯的链增长行为。结果显示:拥有3个等活性伯羟基的三羟甲基乙烷在与辛二酸聚合过程中,先后经历短时间的接枝链增长和长时间的树枝状链增长,最终形成了结构规则,分子量分布窄的树枝状结构。丙三醇同时含有伯羟基和仲羟基,脂肪酶对伯羟基的选择性催化导致其与辛二酸聚合过程中先后经历线型增长、接枝增长和“接枝+树枝状”增长,最终形成高分子量分布的无规树枝状结构。   相似文献   

5.
魏荣宝  李洪波  梁娅 《化学学报》2007,65(19):2151-2154
以1,4-环己二酮、丙二酸二乙酯及多元醇等为原料, 经过两次“一锅煮”法合成了六种二代螺环树形化合物1,2,3,4,5,6,7,8,9,10,11,12-十二氢-2,2;6,6;10,10-三[3,3-二(烷氧羰基)-1,1-环亚丁基二甲氧基]三亚苯基螺环树形化合物, 其中烷氧基为异戊氧基、三羟甲基甲氧基、2,2-二溴甲基-3-羟丙氧基、2,2-二羟甲基丙氧基、二羟甲基膦甲氧基和(N-羟甲基-N-二羟甲基氨基乙基)甲氧基. 利用IR, NMR, MS和元素分析对合成的化合物进行了结构认证, 对影响反应的因素进行了讨论.  相似文献   

6.
以聚乙二醇(PEG)为软段、六亚甲基二异氰酸酯-1,4-丁二醇-二羟甲基丙酸(HDI-BDO-DMPA)为硬段,制备了一系列水性聚氨酯相变储能材料(WPUPCM)。在相变过程中,由于软段PEG由聚合前的固-液相变转化为聚合后的固-固相变,因此,所制备的WPUPCM表现出固-固相变特性。为了研究其固态相变行为的本质和形成机理,揭示该类聚合物的能量贮存和转换机理,应用偏光显微镜、扫描电镜、原子力显微镜、X射线衍射仪分析研究了PEG、WPUPCM在相变过程中的晶体结构变化特征,讨论了WPUPCM固-固相转变的机理。  相似文献   

7.
四水合氯化锰、2-吡啶甲醇和1,1,1-三羟甲基乙烷在乙腈里反应合成出一个七核Mn簇合物[Mn~Ⅱ_3Mn~Ⅲ_4(Cl)_6(hmp)_6(thme)_2]·H_2O·3CH_3CN(1·H_2O·3CH_3CN,hmpH为2-吡啶甲醇,thme H_3为三羟甲基乙烷),并对该化合物进行X射线衍射单晶结构分析、元素分析、红外光谱和磁性研究。1·H_2O·3CH_3CN属于单斜晶系I2/a空间群,配合物核骨架可看成由交替的MnⅡ和MnⅢ离子形成一个六边形,而这个六边形又围绕在1个MnⅢ离子的周围,这种结构类型的配合物以前并没有报道过。磁性研究表明,化合物1·H_2O中MnⅢ与MnⅡ或MnⅢ与MnⅢ离子之间总体是铁磁性耦合的,交流磁化率研究发现该化合物有弱的频率依赖现象。  相似文献   

8.
许多多元醇在270-500K间具有相变焓很大的固-固相变,是一类潜在的固-固相变低温储能物质。2,2-二羟甲基-1,3-丙二醇是一种重要的多元醇,除在化工方面有广泛的应用外,在低温储能方面也有相当乐观的开发前景。它的有关热性质虽已有一些DSC研究报道,但数据精度较差并缺乏系统性。作为系统研究多元醇及其固体溶液热力学性质工作的一部份,本文将报道2,2-二羟甲基-1,3-丙二醇在275—500K间的热容和相变,并根据所测其固-固相变焓数据讨论该物质被破坏的平均氢键键能。  相似文献   

9.
以三羟甲基乙烷为原料,通过脱水反应首先制得3-羟甲基-3′-甲基氧杂环丁烷(HMO).HMO再分别与丙烯腈和二缩三乙二醇单甲醚反应得到两个取代氧杂环丁烷单体3-(2-氰基乙氧基)甲基-和3-[甲氧基(三乙氧基)]甲基-3′-甲基氧杂环丁烷(HMOAN和HMOPEO).再用阳离子开环聚合方法,以BF3.乙醚作催化剂,丁二醇为引发剂,将两类单体共聚即可得到一系列不同组成的共聚物(PAP).利用1H NMR谱图计算了该共聚物中两种不同结构单元的比,结果表明,其与投料比基本吻合.GPC测得该共聚物的数均分子量范围为2 756~5 342,分子量分布为1.26~1.83.DSC测试结果发现,除在225~246 K之间有一个玻璃化转变温度之外,在305~348 K之间还存在一个热转变温度.TGA测得共聚物的分解温度为573 K,远高于目前广泛使用的液体电解质.电导率测试结果表明,AN20的室温电导率可达到1.07×10-5S/cm,353 K时电导率可达到2.79×10-4S/cm,接近实用要求.  相似文献   

10.
以三羟甲基乙烷为原料, 通过脱水反应首先制得3-羟甲基-3'-甲基氧杂环丁烷(HMO). HMO再分别与丙烯腈和二缩三乙二醇单甲醚反应得到两个取代氧杂环丁烷单体3-(2-氰基乙氧基)甲基-和3-[甲氧基(三乙氧基)]甲基-3'-甲基氧杂环丁烷(HMOAN和HMOPEO). 再用阳离子开环聚合方法, 以BF 3\5乙醚作催化剂, 丁二醇为引发剂, 将两类单体共聚即可得到一系列不同组成的共聚物(PAP). 利用 1H NMR谱图计算了该共聚物中两种不同结构单元的比, 结果表明, 其与投料比基本吻合. GPC测得该共聚物的数均分子量范围为2 756~5 342, 分子量分布为1.26~1.83. DSC测试结果发现, 除在225~246 K之间有一个玻璃化转变温度之外, 在305~348 K之间还存在一个热转变温度. TGA测得共聚物的分解温度为573 K, 远高于目前广泛使用的液体电解质. 电导率测试结果表明, AN20的室温电导率可达到1.07×10 -5 S/cm, 353 K时电导率可达到2.79×10 -4 S/cm, 接近实用要求.  相似文献   

11.
An efficient approach to the synthesis of highly congested di, penta and hexacyclic pyrazoles as well as imidazole fragment containing novel heterocyclic molecule has been developed through a carbanion induced transformation of suitably functionalized 2H-pyran-2-ones, benzo[h]chromene and thiochromeno[4,3-b]pyrans. Due to the presence of fluorescence, we report their prime application metal sensor as off/on switching in ferric ions.  相似文献   

12.
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   

13.
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   

14.
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   

15.
An efficient tandem approach for the selective synthesis of 4,5-dihydroimidazo[1,5-a]quinoxalines 6ag and imidazo[1,5-a]quinoxalines 7ah by the reaction of 2-imidazolyl anilines 4ac with aryl aldehydes 5ak under mild reaction conditions is described. Introduction of electron releasing alkyl groups in substrates 4ab was found to be instrumental for the success of the reaction.  相似文献   

16.
The Diels-Alder reactivity of 1,2-heteroborines (H4C4B(H)X, X?=?NH, PH, AsH; O, S, Se) has been computationally explored by means of Density Functional Theory (DFT) calculations. The influence of the HB?=?X fragment on the reactivity of the system has been quantitatively analyzed in detail by means of the so-called Activation Strain Model (ASM) of reactivity. It is found that the interaction between these species and the dienophile is significantly stronger than that computed for their all-carbon isoelectronic counterpart, benzene. In addition, the strain energy plays a key role in the observed reactivity trends. The role of the aromaticity strength of these heteroarenes on the reactivity is also assessed.  相似文献   

17.
A variety of N-aryl and N-alkyl carbazolones were conveniently achieved in good to high yields via Pd2(dba)3-mediated intramolecular coupling of N-substituted α-iodo enaminones under microwave irradiation. The Pd(0)-catalyzed cyclization was found to proceed favorably with the more electron-deficient phenyl ring during the reactions involving unsymmetrical N,N-diaryl α-iodo enaminones. This unique property enables the construction of carbazolone skeleton containing nitro substituted benzenoid ring.  相似文献   

18.
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   

19.
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   

20.
Both substituted 2,4,5,6-tetrahydrocyclopenta[c]pyrazoles and 2,4,5,6-tetrahydropyrrolo[3,4-c]pyrazoles have been synthesized by the 3+2 intramolecular dipolar cycloaddition of nitrilimines to alkynes. This cyclization has been extended to more versatile 3-bromo derivatives by the use of alkynylbromides as dipolarophiles.  相似文献   

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