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1.
合成了16种1,3-双-(介晶基)-1,1,3.3-四甲基二硅氧烷(Ⅱ_(a,b),Ⅲ_(a─g),Ⅲ_j,Ⅳ_(a─f).其化学结构用 ̄1NMR、IR、UV和元素分析表征。通过DSC和偏光显微镜研究了它们的相行为,除Ⅱ_(a,b)、Ⅲ_d和Ⅳ_d外,其余都呈现液晶相变。用X衍射分析研究了1,3-双-(4-甲基偶氮苯氧甲基)-1,1,3,3-四甲基二硅氧烷(Ⅱ_a)的晶体结构。讨论了这些新型硅氧烷化合物的比学结构对液晶相变行为的影响。  相似文献   

2.
研究了1-芳基-4-乙氧羰基-5-氨基-1,2,3-连三唑(1)同甲酰胺、异氰酸磺酰氯以及内酰亚胺醚等的反应,制得5-H-1-芳基-1,2,3-连三唑[4,5-e]嘧啶-4-酮(2a-c)、5-N-甲基-1-芳基-1,2,3-连三唑[4,5-e]嘧啶-4-酮(3a-c)、1-芳基-4-乙氧羰基-5-脲基-1,2,3-连三唑(4a,b)、5-H-1-芳基-1,2,3-连三唑[4,5-e]嘧啶-4,6-二酮(5_(a,b))、1-苯基-1,2,3-连三唑[4,5-e]哌啶[1,2-b]嘧啶-4-酮(6a)、1-苯基-1,2,3-连三唑[4,5-e]氢化吖辛因[1,2-b]嘧啶-4-酮(7a),并经元素分析、红外、核磁共振以及质谱等方法确认了它们的结构,初步筛选了其代表特的生物活性.  相似文献   

3.
姚心侃  谢庆兰 《结构化学》1996,15(3):193-198
三环己基锡O,O’-二(4-氯苯基)二硫代磷酸酯(I),C30H41Cl2(O2PS2Sn,Mr=718.36,单斜晶系,P21/n,a=16.151(2),b=9.4159(1),c=22.987(3),A,β=105.69(1)°,Z=4,Dc=1.418g.cm^-3,R=0.063;二丁基锡双(O,O’-二(4-甲基苯基)二硫代磷酯酯(Ⅱ),C36H46O4P2S4Sn,Mr=851.66  相似文献   

4.
王家喜  杨德育 《结构化学》1996,15(6):473-477
用X-射线晶体结构衍射法测定了双[1-苄基-1-乙基丙基环戊二烯基]二氯化锆[η5-C5H4C(C2H5)2CH2C6H5]2ZrCl2(I)及(1,2-二异丁基-1,2-甲基-乙基桥联)双环戊二烯基二氯化锆[η5-C5H4C(CH3)(C4H9-i)C(CH3)(C4H9-i)C5H4-η5]ZrCl2(Ⅱ)的结构。二者皆为单斜晶系,(I)的空间群为P2/n,a=12.582(3),b=7.992(2),c=14.979(3)A,β=101.68(1)°,V=1474.9(9)A3,Mr=612.84,Z=2,Dx=1.38g/cm3,μ=5.69cm(-1),F(000)=640,R=0.033,Rω=0.036。(Ⅱ)的空间群为Cc,a=13.309(3),b=9.591(1),c=16.449(8)A。β=4.83(3)°,V=209.2(2)A3,Mr=458.63,Z=4,Dx=1.456g/cm3,μ=7.77cm(-1),F(000)=952,R=0.051,Rω=0.061。化合物(I)以重叠式存在,两个苄基处于反式。晶体(Ⅱ)以交叉式存在,甲基、异丁基以反式构象存在。  相似文献   

5.
冯亚青  张晓东 《合成化学》1997,5(3):269-272
由螺[5.5]十一烷-3-酮与硫脲在碘的存在下反应,生成了4,5-二氢螺[苯并[d]噻唑-6-(7H),1′-环己烷]-2-胺(3),3与溴甲基苯基甲酮在苯中缩合得到相应的酮4a~4c,然后在醇中加热环化生成二氢螺[咪唑并[2,1-b]苯并[d]噻唑]化合物5a~5c。新化合物5a~5c的分子组成及结构经元素分析、1HNMR、13CNMR证实,其中产物5b的分子结构经X-射线衍射晶体分析确认。  相似文献   

6.
合成了9种具L-氨基酸衍生物结构的介晶化合物(I-Ⅲ,Ⅳab,Ⅴa,b,Ⅵa,b)、4种氨基酸衍生物(A1-4)和6种介晶化合物(M1-6).新化合物(Ⅰ-Ⅲ,Ⅳa,b,Ⅴa,b,Ⅵa,b,A4,M3-6)的化学结构通过IR、1HNMR和元素分析证实;并用偏光显微观察和DSC分析研究了其相变行为,结果表明有8种化合物(M3-6,Ⅵa,b,Ⅴb,Ⅵb)呈现液晶相变。测定了它们的比旋光度。通过X射线衍射研究了化合物Ⅵh120~130℃和Ⅵb170~180℃的近晶结构,Ⅵb显,Ⅵb呈。测定了化合物Ⅳb的电滞回线,证明其具铁电性。  相似文献   

7.
二苯膦基锂与6,6-二甲基富烯发生环外双键的加成反应,生成含膦取代环戊二烯基负离子(Ⅰ),它与FeCl2络合,生成1,1',二(1-二苯膦基-异丙基)茂铁(Ⅱ)。(Ⅱ)与PdCl2(PhCN)2反应,生成杂双核络合物(Ⅲ)。茂铁(Ⅱ)为单斜晶系,空间群P21/c,晶胞参数a=1.3382(5)nb,b=0.8550(1)nm,c=1.7309(4)nm,β=109.16(2)°,V=1.87082  相似文献   

8.
三环己基锡O,O'-二(4-氯苯基)二硫代磷酸酯(Ⅰ),C_(30)H_(41)Cl_2O_2PS_2Sn,M_r=718.36,单斜晶系,P2_1/n,a=16.151(2),b=9.415(1),c=22.987(3),β=105.69(1)°,Z=4,Dc=1.418g·cm ̄(-3),R=0.063;二丁基锡双[O,O'-二(4-甲基苯基)二硫代磷酸酯](Ⅱ),C_(36)H_(46)O_4P_2S_4Sn,M_r=851.66,单斜晶系,P2_1/c,a=12.284(4),b=9.807(1),c=34.471(8),β=99.02(2)°,Z=4,D_c=1.379g·cm(-3),R=0.042。化合物Ⅰ具有单分子的四配位变形四面体结构。其Sn-S(1)键长为2.501(2);而Sn与S(2)的原子间距则为3.597;化合物Ⅱ具有单分子的六配位变形八面体结构,其Sn-S(1),Sn-S(2),Sn-S(3)和Sn-S(4)的键长分别为2.495(3),2.493(2),3.244(4)和3.228(3)。  相似文献   

9.
本文利用过渡金属的亲硫性,通过Cp*-W(CO)3Cl(Cp*=C5H5,C5H4CH3)与HFe2Co(CO)9(μ3-S)反应,得到四种含硫异核金属羰基原子簇化合物Cp*WFeCo(CO)8(μ3-S)(Cp*=C5H5,Ⅰ-a;Cp*=C5H4CH3,Ⅱ-a),(Cp*W)2Fe(CO)7(μ3-S)(Cp*=C5H5,Ⅰ-b;Cp*=C5H4CH3,Ⅱ-b)。对合成的簇合物进行了IR,1H/13C-NMR,C/H及金属分析,并对Ⅰ-a进行了X-射线单晶结构分析。  相似文献   

10.
通过SnCl_2对化合物Me_2Si[η~5-C_5H_4Fe(CO)]_2(μ-CO)_2(Ⅰ)中Fe-Fe键的插入反应以及Ⅰ被Na-Hg齐还原所生成的相应双铁负离子{Me_2Si[η~5-C_5H_4Fe(CO)_2]_2}~(2-)与SnR_2Cl_2(R=Me,Ph)的亲核反应,合成了环状化合物Me_2Si[η~5-C_5H_4Fe(CO)_2]_2SnR_2[R=Cl(1),Me(2),Ph(3)]。以元素分析、IR和~1HNMR谱表征了它们的结构,并用X射线衍射测定了配合物3的晶体结构。3为单斜晶系,空间群P2_1/n,a=1.0384(3)nm,b=1.6384(1)nm,c=1.5762(5)nm,β=97.93(2)°,V=2.656(2)nm~3,Z=4,Dx=1.71g/mL。  相似文献   

11.
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   

12.
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   

13.
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   

14.
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   

15.
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   

16.
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   

17.
Synthesis of substituted pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles from the Morita-Baylis-Hillman derivatives of acrylates via saponification followed by Curtius reaction is described.  相似文献   

18.
用正丁胺作为碳源,采用射频辉光放电制备碳膜,选用激光染料R6G和聚乙二醇混合液作为蒸气源,采用单源热蒸发,在蒸发室与染料同时沉积得到混合膜,用拉曼光谱和红外光谱分析了碳膜的结构和键合方式,分析表明:碳膜中存在胺基团和氢原子.混合膜的荧光谱测量结果表明,认为正丁胺对染料荧光谱的影响是因为胺基和氢原子的存在.  相似文献   

19.
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   

20.
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   

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