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1.
研究了在9.84 – 11.80 eV光子能量范围内1-丙醇和2-丙醇的光电离和离解光电离,测量了1-丙醇离解电离产生的碎片离子CH3CH2CH2OH+, CH3CH2CHOH+, CH2CH2OH+, CH3CH2CH2+, CH3CH=CH2+和CH2OH+及2-丙醇离解电离产生的碎片离子CH3CH(OH)CH3+, CH3C(OH)CH3+, CH3CHOH+, CH2=CHOH+, CH3CHCH3+和CH3CH=CH2+的光电离效率谱,得到了这些离子的出现势。结合从头算理论计算,给出了1-丙醇的碎片离子CH3CH2CHOH+, CH2CH2OH+, CH3CH2CH2+, CH3CH=CH2+, CH2OH+和2-丙醇的碎片离子CH3C(OH)CH3+, CH3CHOH+, CH2=CHOH+, CH3CHCH3+, CH3CH=CH2+等的解离通道和解离能。理论计算结果与实验结果符合得很好。  相似文献   

2.
The thermodynamic properties of the reaction of amide and formaldehyde were calculated via B3LYP method when substituents chosen included CH3,CH2CH3,CH2CH2CH3,CH2CH2CH2CH3,CH(CH3)2,CH2CH(CH3)2,CH(CH3)CH2CH3 and C(CH3)3.Based on the optimization of the structures for reactants and products,the thermodynamic functions of all the species for an actual state were obtained.The thermodynamic data and the equilibrium constants were investigated within a temperature range of 300―343.15 K.The calculated results show that the reaction is exothermic and spontaneous.The trends of all thermodynamic properties are consistent with the temperature.The preferential order of the substituent effect is CH2CH(CH3)2CH(CH3)CH2CH3CH2CH2CH2CH3 CH2CH2CH3CH2CH3≈CH(CH3)2C(CH3)3≈CH3.  相似文献   

3.
配体C9H7R(R=CH2CH2CH3(1),CH(CH3)2(2),C5H9(3),CH2C6H5(4),CH2CH=CH2(5))分别与Ru3(CO)12在二甲苯或庚烷中加热回流,得到了6个双核配合物[(η5-C9H6R)Ru(CO)(μ-CO)]2(R=CH2CH2CH3(6),CH(CH3)2(7),C5H9(8),CH2C6H5(9),CH2CH=CH2(10))和[(η5-C9H6)(H3CH2C)CHCH(CH2CH3)(η5-C9H6)][Ru(CO)(μ-CO)]2(11)。通过元素分析、红外光谱、核磁共振氢谱对配合物的结构进行了表征,并用X-射线单晶衍射法测定了配合物6,9,10和11的结构。  相似文献   

4.
2,3-苯并-10-氮杂-1,4,7,13-四氧杂-环十五-2-烯与溴代烃或溴代多甘醇单烷基醚, 在无水碳酸钾存在下, 在乙腈中缩合制得N-取代-2,3-苯并-10-氮杂-1,4,7,13-四氧杂-环十五-2-烯化合物(1-11), 取代基为:n-C4H9, i-C5H11,n-C7H15, CH2CH2OCH3, CH2CH2OCH2CH3, CH2CH2OC4H9, (CH2CH2O)CH3, (CH2H2O)2C2H5, (CH2CH2O)2C4H9, CH2CH=CH2, 和CH2Ph。本文还考查了化合物2-4和6-11在室温下, 在氯仿-水体系中, 对苦味酸碱金属(Li^+、Na^+和K^+)盐的配合作用。  相似文献   

5.
吴成泰  鲁天保 《化学学报》1990,48(4):377-381
2,3-苯并-10-氮杂-1,4,7,13-四氧杂-环十五-2-烯与溴代烃或溴代多甘醇单烷基醚, 在无水碳酸钾存在下, 在乙腈中缩合制得N-取代-2,3-苯并-10-氮杂-1,4,7,13-四氧杂-环十五-2-烯化合物(1-11), 取代基为:n-C4H9, i-C5H11,n-C7H15, CH2CH2OCH3, CH2CH2OCH2CH3, CH2CH2OC4H9, (CH2CH2O)CH3, (CH2H2O)2C2H5, (CH2CH2O)2C4H9, CH2CH=CH2, 和CH2Ph。本文还考查了化合物2-4和6-11在室温下, 在氯仿-水体系中, 对苦味酸碱金属(Li^+、Na^+和K^+)盐的配合作用。  相似文献   

6.
合成了5个新的二丙炔醇酯类化合物[(CO2CH2C≡CH)2(1),CH2(CO2CH2C≡CH)2,(2),(CH2CO2CH2C≡CH2)(3),(CHCO2CH2C≡CH)2,(4),C6H4-1,4-(CO2CH2C≡CH)2,(5)],并对其进行了C/H,IR和^1H NMR等表征。  相似文献   

7.
本文合成了9种含有由天然D( )鄄樟脑衍生的1R,3S鄄1,2,2鄄三甲基鄄1,3鄄环戊二胺(A)为配体的铂髤配合物[Pt髤AX]{其中,X=(CH2)3C(COO-)2(1,1鄄环丁烷二羧酸根),2CH3OCH2COO-,2CH3CH2OCH2COO-,2CH3(CH2)3OCH2COO-,[OCH(CH3)COO]2-(乳酸根),(OCH2COO)2-(乙醇酸根),2CH3OCH2CH2OCH2COO-,2CH3CH2OCH2CH2OCH2COO-和2CH3(CH2)3OCH2CH2OCH2COO-}。通过元素分析、热重分析、红外光谱、1H核磁共振谱和电喷雾质谱等对配合物进行了表征。体外生物活性测试表明,部分配合物对A549人肺癌细胞和HCT鄄116人结肠癌细胞具有较强的抗肿瘤活性。  相似文献   

8.
本文合成了9种含有由天然D(+)-樟脑衍生的1R,3S-1,2,2-三甲基-1,3-环戊二胺(A)为配体的铂(Ⅱ)配合物[Pt(Ⅱ)AX]{其中,X=(CH2)3C(COO-)2(1,1-环丁烷二羧酸根),2CH3OCH2COO-,2CH3CH2OCH2COO-,2CH3(CH2)3OCH2COO-,[OCH(CH3)COO]2-(乳酸根),(OCH2COO)2-(乙醇酸根),2CH3OCH2CH2OCH2OO-,2CH3CH2OCH2CH2OCH2COO-和2CH3(CH2)3OCH2CH2OCH2COO-).通过元素分析、热重分析、红外光谱、1H核磁共振谱和电喷雾质谱等对配合物进行了表征.体外生物活性测试表明,部分配合物对A549人肺癌细胞和HCT-116人结肠癌细胞具有较强的抗肿瘤活性.  相似文献   

9.
以Keggin结构的磷钨酸、硅钨酸为电子受体,高分子聚乙烯亚胺(PEI)为电子给体,合成了两种新型电荷转移配合物CH2CH2N(CH2CH2NH2)CH2CH2NHCH2CH2NH2.1H3PW12O40·10.6H2O(配合物Ⅰ)和CH2CH2N(CH2CH2NH2)CH2CH2NHCH2CH2NH1.3H4SiW12O40·8.3H2O(配合物Ⅱ)。采用元素分析、红外光谱和紫外光谱进行表征,并用扫描电镜观察产物形貌及其聚集形态。结果表明有机给体与杂多酸间有较强的相互作用。光致变色后,配合物中有机阳离子和杂多阴离子之间发生了电荷转移,导致杂多阴离子中WⅥ还原为WⅤ,同时有机阳离子被氧化,且该配合物有很高的耐溶剂性。  相似文献   

10.
采用密度泛函理论(DFT)研究了螺桨烷型分子BX[(CH2)n]3和BX(CH2)[CH(CH2)n CH](X=N,P;n=1-6)的结构、稳定性、化学键和电子光谱性质.计算结果表明这些分子都是稳定的.BX[(CH2)n]3(X=N,P;n=1-6)的最高占据分子轨道(HOMO)和最低空分子轨道(LUMO)之间的能隙均大于5.20 eV,其中BN[CH2]3和BP[CH2]3的能隙超过7.0 eV,与C5H6的能隙(7.27 eV)很接近,BX(CH2)[CH(CH2)n CH](X=N,P;n=1-6)的能隙在6.80 eV左右.所研究分子能量的二阶差分表明BN[(CH2)3]3、BP[(CH2)4]3及BX(CH2)[CH(CH2)2CH](X=N,P)是最稳定的.BX[(CH2)n]3的Wiberg键级表明除了BN[(CH2)n]3(n=2和6)中不存在B―N键,其它化合物中B和N均形成了化学键,BP[(CH2)n]3中除了BP[(CH2)2]3不存在B―P键,其它的均存在.电子密度的拓扑分析表明N―B键属于离子键,而P―B键具有共价键特征.BX[(CH2)n]3(X=N,P)的第一垂直激发能分别在191.1-284.8 nm和191.8-270.1 nm之间,BX(CH2)[CH(CH2)n CH](X=N,P)的第一垂直激发能分别在190.5-199.7 nm和209.0-221.3 nm之间.  相似文献   

11.
本文用自由基捕捉剂2,3,5,6-四甲基亚硝基苯(ND)与ESR相结合的方法研究了四氯乙烯光解活泼自由基及其与烃或醇的夺氢反应, 结果表明:1. Cl_2C=CCl_2光解首先产生Cl_2C=CCl及Cl, 而又可进一步加成为Cl_2C-CCl_3.2. 对于CH_3(CH_2)_nOH(n=3,7)及(CH_3)_2CH(CH_2)_nOH(n=1,2)而言, Cl_2C=CCl(或Cl)分别夺取其α-碳及叔碳上的氢, 以形成CH_3(CH_2)_(n-1)CHOH及(CH_3)_2C(CH_2)_nOH, 并为ND所捕获。3. Cl_2C=CCl(或Cl)分别夺取CH_3(CH_2)_nCH3(n=3,4,5,6), C_6H_5-CH_2CH_3及(CH_3)_2CH(CH_2)_nCH_3(n=1,4), (C_2H_5)_2CHCH_3, C_6H_5CH(CH_3)_2中亚甲基及叔碳上的氢, 以形成CH_3(CH_2)_mCH(CH_2)_(n-m-1)CH_3, C_6H_5CHCH_3及(CH_3)_2C(CH_2)_nCH_3, (C_2H_5)_2CCH_3, C_6H_5C(CH_3)_2.  相似文献   

12.
The hemilabile chiral C2 symmetrical bidentate substituted amide ligands (1R,2R)-5(a-d) and (1S,2S)-6(a-d) were synthesized in quantitative yield from (1R,2R)-(+)-3-methylenecyclo-propane-1,2-dicarboxylic acid (1R,2R)-3 and (1S,2S)-(-)-3-methylene-cyclopropane-1,2-dicarboxylic acid (1S,2S)-3, in two steps, respectively. The chiral Feist's acids (1R,2R)-3 and (1S,2S)-3 were obtained in good isomeric purity by resolution of trans-(±)-3-methylene-cyclopropane-1,2-dicarboxylic acid from an 8:2 mixture of tert-butanol and water, using (R)-(+)-α-methylbenzyl amine as a chiral reagent. This process is reproducible on a large scale. All these new synthesized chiral ligands were characterized by 1H-NMR, 13C-NMR, IR, and mass spectrometry, as well as elemental analysis and their specific rotations were measured. These new classes of C2 symmetric chiral bisamide ligands could be of special interest in asymmetric transformations.  相似文献   

13.
Diastereomeric meso- and d,l-bis(bicyclopropylidenyl) (5) were obtained upon oxidation with oxygen of a higher-order cuprate generated from lithiobicyclopropylidene (4) in 50 and 31 % yield, respectively. Their perdeuterated analogues meso-[D(14)]- and d,l-[D(14)]-5 were obtained along the same route from perdeuterated bicyclopropylidene [D(8)]-3 (synthesized in six steps in 7.4 % overall yield from [D(8)]-THF) in 20.5 % yield each. Dehalogenative coupling of 1,1-dibromo-2-cyclopropylcyclopropane (6) gave a mixture of all possible stereoisomers of 1,5-dicyclopropylbicyclopropylidene 16 in 69 % yield, from which (Z)-cis-16 was separated by preparative gas chromatography (26 % yield). The crystal structure of meso-5 looks like a superposition of the crystal structures of two outer bicyclopropylidene units (3) and one inner s-trans-bicyclopropyl unit, whereas the two outer cyclopropyl moieties adopt a gauche orientation with respect to the cyclopropane rings at the inner bicyclopropylidene units in (Z)-cis-16. Birch reduction with lithium in liquid ammonia of meso-5 and d,l-5 gave two pairs of diastereomeric quatercyclopropanes trans,trans-(R*,S*,R*, S*)-17/cis,trans-(R*,S*,R*,R*)-18 and trans,trans-(R*,S*,S*,R*)-19/cis,trans-(R*,S*,S*,S*)-20 in 97 and 76 % yield, respectively, in a ratio 9:1 for every pair. The latter diastereomer was also obtained as the sole product by Birch reduction of (Z)-cis-16 in 96 % yield. Under the same conditions, tetradecadeuterio analogues trans,trans-[D(14)]-(R*,S*,R*,S*)-17/cis,trans-[D(14)]-(R*, S*,R*,R*)-18 (8:1) and trans,trans-[D(14)]-(R*,S*,S*,R*)-19/cis,trans-[D(14)]-(R*,S*,S*,S*)-20 (12:1) were prepared from meso-[D(14)]-5 and d,l-[D(14)]-5 in 37 and 63 % yield, respectively. Reduction of meso-5 with diimine gave the cis,cis-quatercyclopropane (S*,S*,R*,R*)-21 as the main product (58 % yield) along with the cis,trans-diastereomer (S*,S*,R*,S*)-18 (29 % yield). Thus, five of the six possible diastereomeric quatercyclopropanes were obtained from meso-5, d,l-5, and (Z)-cis-16. The X-ray crystal structure analyses of trans,trans-(R*,S*,R*,S*)-17 and cis,cis-(S*,S*,R*,R*)-21 revealed for the both an unusual conformation in which the central bicyclopropyl unit adopts an s-trans-(antiperiplanar) orientation with phi=180.0 degrees , and the two terminal bicyclopropyl moieties adopt a synclinal conformation with phi=49.8 and 72.0 degrees , respectively. In solution the vicinal coupling constants (3)J(H,H) in trans,trans-(R*,S*,R*,S*)-[D(14)]-17, trans,trans-(R*,S*,S*,R*)-[D(14)]-19, trans,cis-(R*,S*,R*,R*)-[D(14)]-18 and trans,cis-(R*,S*,S*,S*)-[D(14)]-20 were found to be 4.1, 4.7, 5.9 and 5.9 Hz, respectively. This indicates a predominance of the all-gauche conformer in (R*,S*,R*,S*)-17 and a decreasing fraction of it in this sequence of the other diastereomers.  相似文献   

14.
Chiral cycloalkane-trans-1,2-diols (+/-)-3 and (+/-)-8 having a diester moiety have been prepared from dimethyl dialkenylmalonate using olefin metathesis by Grubbs catalyst, followed by epoxidation and acidic hydrolysis. Kinetic resolution of racemic cyclopentane-trans-1,2-diol (+/-)-3 by lipase-catalyzed transesterification afforded an optically active monoacetate (-)-5 of 95% ee in 46% yield and the recovered diol (-)-3 of 92% ee in 51% yield, and that of cycloheptane-trans-1,2-diol (+/-)-8 gave a monoacetate (+)-10 of 95% ee in 51% yield and the diol (-)-8 of >99% ee in 43% yield, respectively. The enantiomer selectivity of racemic cyclic trans-1,2-diols bearing a diester moiety by lipases (Amano PS and Amano AK) was opposite to that of the reported simple racemic cycloalkane-trans-1,2-diols. To explain the lipase-catalyzed enantiomer selectivity, computer modeling of lipase-substrate complexes was performed. Furthermore, the optically active diester (-)-8 could be efficiently converted into an optically active seven-membered-ring alpha,alpha-disubstituted amino acid (4R,5R)-(-)-15.  相似文献   

15.
Oxidation of trans-3,5-di-tert-butyl-3,5-diphenyl-1,2,4-trithiolane with dimethyldioxirane (DMD) or m-chloroperbenzoic acid (MCPBA) gave two stereoisomeric (1S*,3S*,5S*)- and (1R*,3S*,5S*)-1-oxides (16 and 17, respectively). Oxidation of 16 with DMD gave the (1S*,2R*,3S*,5S*)-1,2-dioxide (18) and the 1,1-dioxide 19, and that of 17 yielded the (1R*,2R*,3S*,5S*)-1,2-dioxide (20) mainly along with 18 and 19. The structures of the 1,2-dioxides 18 and 20 were determined by X-ray crystallography. 1,2-Dioxides 18 and 20 isomerized to each other in solution, and the equilibrium constant K (20/18) is 19 in CDCl(3) at 295 K. The kinetic study suggested a biradical mechanism for the isomerization. Isomerization of 16 and 17 to cis-3,5-di-tert-butyl-1,2,4-trithiolane 1-oxides by treatment with Me(3)O(+)BF(4)(-) is also described.  相似文献   

16.
The frustrated Lewis pair B(C(6)F(5))(3)/P(o-tolyl)(3) (4a) reacts with 4,6-decadiyne to give the trans-1,2-addition product 5. In contrast, the B(C(6)F(5))(3)/P(t)Bu(3) FLP (4b) reacts with this substrate to give the trans-1,4-adduct trans-6. The cumulene trans-6 undergoes trans-/cis-isomerization upon photolysis to give a ca. 1:1 trans-6/cis-6 mixture. The FLP 4b reacts with 2,6-hexadiyne at r.t. to yield a ca. 4:1 mixture of their trans-1,2- and trans-1,4-addition products (7,8). DFT calculations showed that the zwitterionic 1,4-addition products are favored under thermodynamic control. Thermolysis of the kinetic trans-1,2-addition product (7) (80 °C, bromobenzene) does not lead to the thermodynamically favored 1,4-isomer (8), but instead elimination of isobutylene occurs to the formal trans-1,2-adduct (9) of the B(C(6)F(5))(3)/PH(t)Bu(2) pair. Compounds 5, 6, 7, 8, 9 were analyzed by X-ray diffraction.  相似文献   

17.
Acid-catalyzed intramolecular addition of a hydroxy group to alpha-alkylated vinylsilanes has been studied. Treatment of (Z)-5-alkyl-5-silyl-4-penten-1-ols 1 (R = alkyl) with 5 mol % TiCl(4) in CHCl(3) gave trans-2-alkyl-3-silyltetrahydropyrans 2 exclusively (trans/cis = >99/1 to 97/3). The cyclization efficiency and rate strongly depended on the geometry of the C-C double bond and the silyl group. The use of (E)-vinylsilanes resulted in lower yields with poor cis-selectivity. In the cyclization of (Z)-1 (R = Bu), the silyl group used, the reaction time, and the yield of 2 were as follows: SiMe(2)Ph, 9.5 h, 75%; SiMe(3), 7.5 h, 66%; SiMePh(2), 24 h, 58%; SiMe(2)-t-Bu, 0.75 h, 85%; SiMe(2)Bn, 1.5 h, 78%. This 1,2-silyl-migrative cyclization could be applied to stereoselective synthesis of trisubstituted tetrahydropyrans. The acid-catalyzed reaction of 1-, 2-, or 3-substituted (Z)-5-silyl-4-nonen-1-ols 8 gave r-2,t-3,c-6-, r-2,t-3,t-5-, or r-2,t-3,c-4-trisubstituted tetrahydropyrans with high diastereoselectivity, respectively. (Z)-4-Alkyl-4-silyl-3-buten-1-ols 5 as well as 1 underwent the 1,2-silyl-migrative cyclization to give 2-alkyl-3-silyltetrahydrofurans 6 with high trans-selectivity. This silicon-directed cyclization was also available for the stereoselective synthesis of tri- and tetrasubstituted tetrahydrofurans.  相似文献   

18.
Lithium tetrabutylaluminate modified by either (-)-N-methylephedrine or Darvon alcohol[(*)-(2S, 3R)-4-dimethylamino-3-methyl-1,2-diphenyl-2-butanol] readily reacts with phenylglyoxylic acid methyl ester to give the expected α-butyl α-hydroxy ester with a good chemical yield and an optical yield of 43% when Darvon alcohol is used.  相似文献   

19.
Reaction of the methyl iodide of trans-1,2,5-trimethyl-4-piperidone with S--phenylethylamine proceeds asymmetrically and leads in 66% optical yield to the formation of the cis- and trans-diastereomeric pair of 1-(-phenylethyl)-2,5-dimethyl-4-piperidone, in which the new asymmetric centers possess the 2S,5S- and 2S,5R-configurations, respectively. According to x-ray structural analysis, the minor trans-1-(-phenylethyl)-2,5-dimethyl-4-piperidone component possesses the 2R,5S-configuration. The occurrence of asymmetric synthesis accompanying transamination was confirmed via the preparation of enantiomers of trans-2,5- and trans-1,2,5-trimethyl-4-piperidones.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1641–1648, December, 1986.  相似文献   

20.
[reaction: see text] (3R,5R)-1 R1 & R2 = TBDPS, (3S,5R)-2 R1 = Bn,R2 = TBDPS, (3S,5S)-3 R2 & R2 = Bn. trans-3,5-Bis(benzyl/tert-butyldiphenylsilyloxymethyl)morpholines, promising candidates for the C(2)-symmetric class of chiral reagents, were prepared with excellent optical purity. A key step in the synthesis is the coupling of a serinol derivative with 2,3-O-isopropylideneglycerol triflate or its equivalent. This methodology was extended to the synthesis of chiral trans-3-(benzyloxymethyl)-5-(tert-butyldiphenylsilyloxymethyl)morpholine, a potentially useful chiral building block.  相似文献   

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