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1.
杨益琴  李艳苹  王石发  谷文 《有机化学》2009,29(7):1092-1095
以(1S,5S)-(-)-α-蒎烯为原料合成了系列新型(1S,2S,3S,5R)-N-烷基-3-蒎胺类化合物. (-)-α-蒎烯经硼氢化氧化、重铬酸吡啶盐(PDC)氧化得到(1S,2S,5R)-(-)-3-蒎酮; 在BF3•(C2H5)2O催化下(1S,2S,5R)-(-)-3-蒎酮与伯胺化合物反应生成Schiff碱, 再经KBH4或NaBH4还原得到(1S,2S,3S,5R)-N-烷基-3-蒎胺类化合物. 采用FT-IR, 1H NMR, 13C NMR和GC-MS等分析手段对合成所得(1S,2S,5R)-N-烷基-3-蒎烷亚胺和(1S,2S,3S,5R)-N-烷基-3-蒎胺类化合物的结构进行了表征. 考察了(1S,2S,3S,5R)-N-烷基-3-蒎胺类化合物对大肠杆菌(E. coli)、金黄色葡萄球菌(S. aureus)、枯草芽胞杆菌(B. subtilis)、荧光假单胞菌(P. fluorescens)、白色念珠菌(C. albicans)、黑曲霉(A. niger)和米根霉(R. oryzae)等细菌和真菌的抑菌和杀菌活性. 结果表明(1S,2S,3S,5R)-N-正庚基-3-蒎胺对真菌和细菌均表现出良好的杀菌和抑菌活性.  相似文献   

2.
Function of a new N-heterocyclic carbene ligand based on the concept of a chiral mimetic is described. With (4R,5R)-4,5-diphenyl-1,3-dialkyl-4,5-dihydro-3H-imidazol-1-ium tetrafluoroborates as N-heterocyclic carbene precursors, Rh-catalyzed enantioselective arylation (up to 27% ee) of aromatic aldehydes with arylboronic acids and Pd-catalyzed enantioselective intramolecular alpha-arylation (up to 66% ee) of N-(2-bromoaryl)-N-alkyl-2-arylpropanamides are investigated.  相似文献   

3.
《Tetrahedron letters》1986,27(2):123-126
The use of a new sulfamoylation reagent, N-carbo-(trimethylsilyloxy)sulfamoyl chloride (3) has led to an abbreviated and high yielding preparation of 3-amino-4-N-alkyl-5-aryloxy-1,2,4,6-thiatriazine-l, 1-dioxides (1). A related approach to the 2-N-alkyl isomer (2) is described.  相似文献   

4.
Conclusions A general method was developed for the synthesis of a previously unknown class of 1-N-alkyl-2-ethynylpiperazines from 1,4-dibronio-1,2-butadiene.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No.1, pp.124–128, January, 1976.  相似文献   

5.
Conclusions Starting with 1,4-dibromo-1,2-butadiene we synthesized bis(1-bromo-1,2-butadienyl)-N-(-hydroxyethyl)amine, which was reacted with primary amines to give 2,6-diethynyl-1-N-alkyl-4-N-(-hydroxyethyl)piperazines.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp. 2579–2582, November, 1975.  相似文献   

6.
(E)-N-alkyl-4-(2-(4-dimethylaminophenyl)ethenyl) pyridinium bromides (hemicyanine bromides) with C14, C16 and C18 straight alkyl chains are described. The thermal behaviour of these compounds was investigated by differential scanning calorimetry (DSC) and by optical microscopy. The textures observed in polarised light revealed that these compounds exhibit a smectic A mesophase. A focal-conic fan texture was observed, together with regions showing homeotropic alignment. The phase behaviour of the compound with the C16 chain can be summarized as: Cr1·99·Cr2·249·SmA·268·I (dec.). The transition temperatures are rather independent of the length of the alkyl chain. The compounds have a strong tendency to supercool to a glassy mesophase. A structural model for the mesophase is proposed. The bromide anion of the hemicyanine bromides can be replaced by the bulky tetrakis(-diketonato)lanthanide(III) anion. As the -diketone, 2,4-pentanedione (acetylacetone, acac) and 1,3-diphenyl-1,3-propanedione (dibenzoylmethane, DBM) are chosen. None of the lanthanide complexes containing the hemicyanine chromophore shows a mesophase. The complexes either melt directly to an isotropic liquid, or decompose without melting.  相似文献   

7.
The singlet ground ((approximate)X(1)Sigma1+) and excited (1Sigma-,1Delta) states of HCP and HPC have been systematically investigated using ab initio molecular electronic structure theory. For the ground state, geometries of the two linear stationary points have been optimized and physical properties have been predicted utilizing restricted self-consistent field theory, coupled cluster theory with single and double excitations (CCSD), CCSD with perturbative triple corrections [CCSD(T)], and CCSD with partial iterative triple excitations (CCSDT-3 and CC3). Physical properties computed for the global minimum ((approximate)X(1)Sigma+HCP) include harmonic vibrational frequencies with the cc-pV5Z CCSD(T) method of omega1=3344 cm(-1), omega2=689 cm(-1), and omega3=1298 cm(-1). Linear HPC, a stationary point of Hessian index 2, is predicted to lie 75.2 kcal mol(-1) above the global minimum HCP. The dissociation energy D0[HCP((approximate)X(1)Sigma+)-->H(2S)+CP(X2Sigma+)] of HCP is predicted to be 119.0 kcal mol(-1), which is very close to the experimental lower limit of 119.1 kcal mol(-1). Eight singlet excited states were examined and their physical properties were determined employing three equation-of-motion coupled cluster methods (EOM-CCSD, EOM-CCSDT-3, and EOM-CC3). Four stationary points were located on the lowest-lying excited state potential energy surface, 1Sigma- -->1A", with excitation energies Te of 101.4 kcal mol(-1) (1A"HCP), 104.6 kcal mol(-1)(1Sigma-HCP), 122.3 kcal mol(-1)(1A" HPC), and 171.6 kcal mol(-1)(1Sigma-HPC) at the cc-pVQZ EOM-CCSDT-3 level of theory. The physical properties of the 1A" state with a predicted bond angle of 129.5 degrees compare well with the experimentally reported first singlet state ((approximate)A1A"). The excitation energy predicted for this excitation is T0=99.4 kcal mol(-1) (34 800 cm(-1),4.31 eV), in essentially perfect agreement with the experimental value of T0=99.3 kcal mol(-1)(34 746 cm(-1),4.308 eV). For the second lowest-lying excited singlet surface, 1Delta-->1A', four stationary points were found with Te values of 111.2 kcal mol(-1) (2(1)A' HCP), 112.4 kcal mol(-1) (1Delta HPC), 125.6 kcal mol(-1)(2(1)A' HCP), and 177.8 kcal mol(-1)(1Delta HPC). The predicted CP bond length and frequencies of the 2(1)A' state with a bond angle of 89.8 degrees (1.707 A, 666 and 979 cm(-1)) compare reasonably well with those for the experimentally reported (approximate)C(1)A' state (1.69 A, 615 and 969 cm(-1)). However, the excitation energy and bond angle do not agree well: theoretical values of 108.7 kcal mol(-1) and 89.8 degrees versus experimental values of 115.1 kcal mol(-1) and 113 degrees. of 115.1 kcal mol(-1) and 113 degrees.  相似文献   

8.
2-(Pyrazol-1-yl)-, 2-(imidazol-1-yl)-, 2-([1,2,4]triazol-1-yl)-, and 2-(benzotriazol-1-yl)-4,4,5,5-tetramethyl-4,5-dihydro-1H-imidazole-3-oxide-1-oxyl were prepared by reactions of 2-bromo-4,4,5,5-tetramethyl-4,5-dihydro-1H-imidazole-3-oxide-1-oxyl (NIT-Br) with the corresponding sodium azolides. In prepared 2-(azol-1-yl)-4,4,5,5-tetramethyl-4,5-dihydro-1H-imidazole-3-oxide-1-oxyls, the NIT-NHet bond is readily hydrolyzed. Reduction of imidazole-3-oxide-1-oxyls leads to corresponding 2-(azol-1-yl)-4,4,5,5-tetramethyl-4,5-dihydro-1H-imidazole-1-oxyls, which are much more stable against hydrolysis. The structures of spin-labeled imidazoles, [1,2,4]triazoles and benzotriazoles are confirmed by X-ray analysis, showing that the paramagnetic molecules form packings with motifs from centrosymmetric dimers to topologically linear chains.  相似文献   

9.
Two new, more convenient methods for the synthesis of 1,2,4-triazol-5-ylidenes are described. Four new 1,2,4-triazol-5-ylidenes have been prepared using these methods: 1-(1-adamantyl)-3,4-diphenyl-1,2,4-triazol-5-ylidene (2a), 1-(1-adamantyl)-3-phenyl-4-(p-bromophenyl)-1,2,4-triazol-5-ylidene (2b), 1-(1-adamantyl)-3-phenyl-4-(alpha-naphthyl)-1,2,4-triazol-5-ylidene (2c), and 1-(1-adamantyl)-3,4-di(p-bromophenyl)-1,2,4-triazol-5-ylidene (2d). The X-ray crystal structures of 2d and the precursor salt 1-(1-adamantyl)-3,4-di(p-bromophenyl)-1,2,4-triazolium bromide (1e) are described. Compound 2a reacts with CH(3)CN via C-H insertion to form 1-(1-adamantyl)-3,4-diphenyl-5-cyanomethyl-5H-1,2,4-triazoline (3), and 2a and 2d react with elemental sulfur and elemental selenium, respectively, to form the corresponding thione (4) and selenone (5).  相似文献   

10.
A series of chalcones and their derivatives have been synthesized. Chalcones, 1-(1,3-benzodioxol-5-yl)-3-(aryl)-prop-2-en-1-ones were prepared by the aldol condensation of 1-(1,3-benzodioxol-5-yl)ethanones and aryl aldehydes. Based-catalyzed condensation of 1-(1,3-benzodioxol-5-yl)-3-(aryl)prop-2-en-1-ones with ethyl acetoacetate yields corresponding ethyl 4-(1,3-benzodioxol-5-yl)-6-(aryl)-2-oxocyclohex-3-ene-1-carboxylates. Some of the synthesized chalcones were reported in the literature; the newly synthesized compounds were characterized by single crystal X-ray studies, IR, 1H-NMR and LCMS mass spectral analysis.  相似文献   

11.
We have synthesized 1- and 2-(trimethylsilylmethyl)- and 1- and 2-(trimethoxysilylmethyl)benzotriazoles by reaction of 1,2,3-benzotriazolylsodium with trimethyl- or trimethoxy(chloromethyl)silane. We obtained 1- and 2-(silatranylmethyl)benzotriazoles by transesterification of the latter with triethanolamine.  相似文献   

12.
Functionalized o-carboranes are interesting ligands for transition metals. Reaction of LiC2B10H11 with Me2NCH2CH2Cl in toluene afforded 1-Me2NCH2CH2-1,2-C2B10H11 (1). Treatment of 1 with 1 equiv. of n-BuLi gave [(Me2NCH2CH2)C2B10H10]Li ([1]Li), which was a very useful synthon for the production of bisfunctional o-carboranes. Reaction of [1]Li with RCH2CH2Cl afforded 1-Me2NCH2CH2-2-RCH2CH2-1,2-C2B10H10 (R = Me2N (2), MeO (3)). 1 and 2 were also prepared from the reaction of Li2C2B10H10 with excess Me2NCH2CH2Cl. Treatment of [1]Li with excess MeI or allyl bromide gave the ionic salts, [1-Me3NCH2CH2-2-Me-1,2-C2B10H10][I] (4) and [1-Me2N(CH2=CHCH2)CH2CH2-2-(CH2=CHCH2)-1,2-C2B10H10][Br] (6), respectively. Interaction of [1]Li with 1 equiv. of allyl bromide afforded 1-Me2NCH2CH2-2-(CH2=CHCH2)-1,2-C2B10H10 (5). Treatment of [1]Li with excess dimethylfulvene afforded 1-Me2NCH2CH2-2-C5H5CMe2-1,2-C2B10H10 (7). Interaction of [1]Li with excess ethylene oxide afforded an unexpected product 1-HOCH2CH2-2-(CH2=CH)-1,2-C2B10H10 (8). 1 and 3 were conveniently converted into the corresponding deborated compounds, 7-Me2NHCH2CH2-7,8-C2B9H11 (9) and 7-Me2NHCH2CH2-8-MeOCH2CH2-7,8-C2B9H10 (10), respectively, in MeOH-MeOK solution. All of these compounds were characterized by various spectroscopic techniques and elemental analyses. The solid-state structures of 4 and 6-10 were confirmed by single-crystal X-ray analyses.  相似文献   

13.
A series of nitroimidazoles were subjected to hydroxymethylations under a variety of conditions. Hydroxymethylation of 1-(2-hydroxyethyl), 1-(2-acetoxyethyl), and 1-(2-chloroethyl) substituted 5-nitroimidazoles with paraformaldehyde in dimethyl sulfoxide yielded the respective 2-hydroxymethyl analogs (5–7). However, attempts to hydroxymethylate 1-(2-hydroxyethyl), 1-(2-acetoxyethyl), 1-(2-cyanoethyl) substituted 4-nitroimidazoles and 1-(2-hydroxyethyl)-2-nitroimidazole were unsuccessful. Treatment of 1-(2-acetoxyethyl)-5-nitro-2-imidazolecar-baldehyde(10) with hydroxylamine-O-sulfonic acid afforded a mixture of corresponding 2-carbonitrile (12) and 2-(N-hydroxy)carboximidamide (13). Hydrolysis of 10 with ethanolic hydrochloric acid yielded 8-ethoxy-5,6-dihydro-3-nitro-8H-imidazo[2,1-c] [1,4]oxazine (11) which, on subsequent reaction with hydroxylamine-O-sulfonic acid, afforded 1-(2-hydroxyethyl)-5-nitroimidazole-2-(N-hydroxy)carboximidamide (15). Reaction of 4(5)-nitroimidazole with chloropropionitrile produced a mixture of the isomeric 1-(2-cyanoethyl) substituted 4- and 5-nitroimidazoles. Treatment of 2,4(5)-dinitroímidazole with chloropropionitrile afforded a mixture of 4(5)-chloro-5(4)-nitroimidazole and 1-(2-cyanoethyl)-4-nitro-5-chloroimidazoIe. Reaction of nitroimidazoles with acrylonitrile in the presence of Triton B yielded the corresponding 1-(2-cyanoethyl) substituted derivatives.  相似文献   

14.
Mono- and disubstituted benzimidazoles were synthesized during alkaline hydrolysis or reactions with ethyl chloroacetate of 1-phenyl substituted 4-(1H-benzimidazol-2-yl)-2-pyrrolidinones. The properties of the synthesized ethyl-[2-(1-(substituted phenyl)-5-oxopyrrolidinyl-3-yl)-1H-benzimidazolyl]ethanoates have been investigated and their benzimidazolium chlorides, 1-carboxymethylbenzimidazoles, condensation products of 2-{2-[1-(3-methylphenyl)-5-oxo-3-pyrrolidinyl]-1H-benzimidazol-1-yl}acetohydrazide with various aromatic aldehydes and aliphatic ketones have been obtained.  相似文献   

15.
The stereoselective synthesis of both enantiomers of trifluoro frontalin (-)-(1S,5R)- and (+)-(1R,5S)-8, as well as of diastereomeric monofluoro frontalines (-)-(1R,2R,5R)-18 and (-)-(1R,2S,5R)-20, analogues of the bioactive component of the aggregation pheromone of the Scolytidae insect family, has been accomplished starting from (-)-(1R)- and (+)-(1S)-menthyl (S)-toluene-4-sulfinate as a source of chirality and methyl trifluoroacetate or fluoroacetate, respectively, as sources of fluorine. The C-1 stereocenters were installed via stereoselective epoxidation of beta-sulfinyl ketones 2 and 13 with diazomethane. The bicyclic core was obtained by totally stereocontrolled and chemoselective tandem Wacker oxidation/intramolecular ketalization of the intermediate unsatured sulfinyl diols 5, 15, and 19. Axially fluorinated (-)-20 elicited a strong electroantennographic response in laboratory tests on females of Dendroctonus micans, whereas equatorially fluorinated (-)-18 and the trifluoroanalogue (-)-8 showed modest responses. Field trials using (-)-20 were not indicative owing to the locally scarce population of D. micans, but it showed some attractiveness for other Coleoptera families.  相似文献   

16.
The stereoselectivity of the reaction of furan (1) with maleic anhydride (2) and maleimide (3) was studied experimentally and theoretically. Although the two reactions are highly similar with regard to their preference for endo and exo steroisomers, notable differences were experimentally observed and explained on the basis of calculated reaction-free energies and transition-state barriers. The experimental values of rate constants (k(1+2endo) = (1.75 +/- 0.48) x 10(-5); mol(-1) l s(-1); k(1+2exo) = (3.10 +/- 0.55) x 10(-5); mol(-1) l s(-1); k(1+3endo) = (1.93 +/- 0.082) x 10(-5); mol(-1) l s(-1), k(1+3exo) = (1.38 +/- 0.055) x 10(-5); mol(-1) l s(-1) all at 300 K) and the observed reaction course clearly confirm that neither of these reactions are prototypical examples of Diels-Alder [4 + 2] cycloadditions, whose dominant preference is for endo isomers. However, only by comparing their energetics-calculated at the CCSD(T) level of theory-with the analogous reactions involving cyclopentadiene (8) as a diene can these observations be understood. The low thermodynamic stability of furan [4 + 2] adducts opens retro-Diels-Alder reaction channels and overrules the very small kinetic preference (calculated and measured here) of initial formation for endo stereoisomers. On a macroscopic scale "an irregular"-thermodynamically more stable-exo stereoisomer was consequently observed as a dominant species.  相似文献   

17.
N-(1-Adamantyl)-4-(1-hydroxy-1-trifluoromethyl- 2,2,2- trifluoroethyl)aniline (III) and N-(1-adamantyl)-4-(1-hydroxy-1-methoxycarbony 1-2,2,2-trif luoroethyl) aniline (IV) were obtained by the reaction of N-(1-adamantyl)aniline with ketone (I) and ketoester (II). Analogous procedures gave N-(2-adamantyl)- 4- (1-hydroxy- 1-trifluoromethyl- 2, 2,2-trifluoroethyl)aniline (V) and N-(2-adamantyl)-4-(1-hydroxy-1-methoxycarbonyl-2,2,2-trifluoroethyl)aniline (VI). The action of hydrogen peroxide on (III) in the presence of sodium tungstenate gave N- (1- adamantyl)- 4- (1- hydroxy- 1- trifluoromethyl- 2,2,2- trifluoroethyl)aniline N-oxide (VII).Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 10, pp. 2348–2350, October, 1989.  相似文献   

18.
(E)-4-tert-Butyl-4'-oxystilbene, 1(-), is thermally stable as the (E)-1(-) isomer but may be photoisomerized to the (Z)-1(-) isomer as shown by UV-vis and (1)H NMR studies in aqueous solution. When (E)-1(-) is complexed by alphaCD two inclusion isomers (includomers) form in which alphaCD assumes either of the two possible orientations about the axis of (E)-1(-) in alphaCD.(E)-1(-) for which (1)H NMR studies yield the parameters: k(1)(298 K)= 12.3 +/- 0.6 s(-1), DeltaH(1)(++)= 94.3 +/- 4.7 kJ mol(-1), DeltaS1(++)= 92.0 +/- 5.0 J K(-1) mol(-1), and k(2)(298 K)= 10.7 +/- 0.5 s(-1), DeltaH(2)(++)= 93.1 +/- 4.7 kJ mol(-1), DeltaS2(++)= 87.3 +/- 5.0 J K(-1) mol(-1) for the minor and major includomers, respectively. The betaCD.(E)-1(-) complex either forms a single includomer or its includomers interchange at the fast exchange limit of the (1)H NMR timescale. Complexation of 1(-) by N-(6(A)-deoxy- alpha-cyclodextrin-6(A)-yl)-N'-(6(A)-deoxy- beta-cyclodextrin-6(A)-yl)urea, results in the binary complexes 2.(E)-1(-) in which both CD component annuli are occupied by (E)-1(-) and which exists exclusively in darkness and 2.(Z)-1(-) in which only one CD component is occupied by (Z)-1(-) and exists exclusively in daylight at lambda > or = 300 nm. Irradiation of solutions of the binary complexes at 300 and 355 nm results in photostationary states dominated by 2.(E)-1(-) and 2.(Z)-1(-), respectively. In the presence of 4-methylbenzoate, 4(-), 2.(Z)-1(-) forms the ternary complex 2.(Z)-1(-).4(-) where 4(-) occupies the second CD annulus. Interconversion occurs between 2.(Z)-1(-).4(-) and 2.(E)-1(-)+4(-) under the same conditions as for the binary complexes alone. Similar interactions occur in the presence of 4-methylphenolate and 4-methylphenylsulfonate. The two isomers of each of these systems represent different states of a molecular device, as do the analogous binary complexes of N,N-bis(6(A)-deoxy- beta-cyclodextrin-6(A)-yl)urea, 3, [3.(E)-1(-) and 3.(Z)-1(-), where the latter also forms a ternary complex with 4(-).  相似文献   

19.
The gas-phase elimination kinetics of the title compounds have been examined over the temperature range of 310-369 degrees C and pressure range of 50-130 Torr. The reactions, in seasoned vessels, are homogeneous, unimolecular, and follow a first-order rate law. The products are methanol and the corresponding methyl ketene acetal. The rate coefficients are expressed by the Arrhenius equation: for trimethyl orthoacetate, log k1 (s(-1)) = [(13.58 +/- 0.10) - (194.7 +/- 1.2) (kJ mol(-1))](2.303RT)(-1)r = 0.9998; and for trimethyl orthobutyrate, log k1(s(-1)) = [(13.97 +/- 0.37) - (195.3 +/- 1.6) (kJ mol(-1))](2.303RT)(-1)r = 0.9997. These reactions are believed to proceed through a polar concerted four-membered cyclic transition state type of mechanism.  相似文献   

20.
Summary The structures of N-methylnicotone and Py-N-methylmetanicotone are, respectively, 1-methyl-5-(1-methyl-2-pyrrolidinyl)-2(1H)-pyridone and 1-methyl-5-(4-methylamino-1-butenyl)-2(1H)-pyridone.  相似文献   

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