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1.
The first two amino-substituted BEDT-TTF derivatives, aminomethyl-ET (AMET) and aminoethyl-ET (AEET), have been prepared; the critical step in both cases was a hetero Diels-Alder reaction with 1,3-dithiole-2,4,5-trithione. AEET shows expected reactivity towards electrophiles whereas AMET will not react with aryl acid chlorides or sulfonyl chlorides, but amides of AMET can be produced by DCC coupling and mixed anhydride methods.  相似文献   

2.
A variety of 1,3,5-tricarbonyl derivatives were prepared by reaction of 1,3-bis(silyl enol ethers) with acid chlorides under mild conditions. This includes reactions of both aromatic and aliphatic acid chlorides and bis(acid chlorides). The yields vary depending on the type of acid chloride employed.  相似文献   

3.
A simple catalyst precursor prepared in situ from palladium acetate and triphenylphosphine shows high activity for the Suzuki cross-coupling reaction of benzylic bromides and chlorides with aryl boronic acids. The reaction can be carried out at low catalyst loading (0.002-1 mol%) and under mild conditions (room temperature to 80 °C) furnishing diarylmethane derivatives in high yields (86-99%).  相似文献   

4.
An efficient, palladium-catalyzed Hiyama cross-coupling reaction of aryltrifluorosilanes with aryl chlorides has been developed. A wide variety of functionalized biaryl derivatives were isolated in good to excellent yields. The scope of this reaction has also been extended to heteroaryl chlorides, affording the corresponding heterobiaryl compounds in high yields.  相似文献   

5.
Kinetic data for solvolyses of 28 acid chlorides in 97% w/w trifluoroethanol (TFE)-water spanning over 10 (9) in rate constant at 25 degrees C are obtained directly or by short extrapolation from published values. G3 calculations of the energy required for cation formation in the gas phase are validated from proton affinities and from other experimental data. G3 calculations of heterolytic bond dissociation enthalpies (HBDEs) for formation of cations from acid chlorides in the gas phase show the following trends when compared with the solvolysis rate constants: (i) electron-rich sulfonyl chlorides and most carboxylic acid chlorides, including thione derivatives, give a satisfactory linear correlation with a significant negative slope; (ii) most sulfonyl chlorides and some chloroformates and thio derivatives have higher HBDEs and fit another correlation with a small, negative slope. A significant deviation is observed for the acyl series (RCOCl), for which both solvolysis rates and HBDEs increase in the order R = Bu ( t ) < Pr ( i ) < Et < Me. The deviation may be explained either by a prior hydration mechanism or preferably by electrostatic effects on the formation of small cations. The above results of structural effects support independent evidence from solvent effects that cationic ionization reaction pathways (with nucleophilic solvent assistance or S N2 character) are involved in the solvolyses of acid chlorides.  相似文献   

6.
Florian Montel 《Tetrahedron》2008,64(27):6372-6376
A new and efficient methodology for the preparation of novel 7-carboxyl-triazolopyrimidine derivatives via the halogen-metal exchange is described. In addition, we showed that this new method can be useful for the synthesis of amides, esters, and ketones by using different carbamoyl chlorides, isocyanides or acyl chlorides as electrophile.  相似文献   

7.
An improved gas chromatographic method is described for the simultaneous determination of carboxylic acid chlorides and related carboxylic acids used in the production of some commercial semisynthetic penicillins. The acid chloride reacts with diethylamine to form the corresponding diethylamide. Carboxylic acid impurities are converted to trimethylsilyl esters. The two derivatives are separated and quantitated in the same chromatographic run. This method, an extension of the earlier procedure of Hishta and Bomstein (1), has been applied to the acid chlorides used to make oxacillin, cloxacillin, dicloxacillin, and methicillin (Figure 1); it shows promise of application to other acid chlorides. The determination is more selective than the usual titration methods, which do not differentiate among acids with similar pK's. Relative standard deviations of the acid chloride determination are 1.0-2.5%. Residual carboxylic acid can be repetitively determined within a range of 0.6% absolute.  相似文献   

8.
A combination of collisional activation mass spectrometry and low-temperature infrared spectroscopy has been used to monitor the production and isomerization of vinyl- and methylene-ketenes. Vinyl- and 2-propenyl-ketenes were produced by flash vacuum pyrolysis of β,γ-unsaturated acid chlorides. Vinyl(carboxyl)ketenes, vinylketenes and methyleneketenes were obtained from Meldrum's acid derivatives (5-alkylidene-1,3-dioxane-4,6-diones). The formation of methyleneketenes by pyrolysis of α, β-unsaturated acid chlorides is only indicated in the mass spectrometry experiments. Carbonylcyclopropane was obtained by pyrolysis of cyclopropylcarbonyl chloride or the corresponding Meldrum's acid derivative. The methyleneketenes isomerize to vinylketenes in the gas phase, particularly under conditions involving long contact times. Carbonylcyclopropane thermally decarbonylates to allene, not methylacetylene. Molecular ions of vinylketenes are obtained via pyrolysis of either acid chlorides or Meldrum's acid derivatives. Molecular ions of alkylmethyleneketenes are obtained pure only by electron impact induced fragmentation of Meldrum's acid derivatives.  相似文献   

9.
Appropriately protected guanosine derivatives were successfully converted to the corresponding O6-substituted guanosine derivatives by treatment with dialkyl- or diaryl-phosphoryl halides, dialkyl- or diaryl-phosphinothioyl halides, arenesulfonyl chlorides, and trialkylsilyl chlorides.  相似文献   

10.
Jing Wang  Yan-Bo Yu  Xingang Zhang 《Tetrahedron》2018,74(44):6329-6334
A palladium catalyzed cross-coupling of fluorinated benzothiadiazoles (FBTs) with allyl chlorides is reported. The significant feature of this method is synthetic simplicity, providing a straightforward access to unsymmetrical and symmetrical alkylated FBT derivatives that are of interest in organic electronic and optoelectronic materials.  相似文献   

11.
 Thiatetraazaindenone derivatives were synthesized by reaction of 3-substituted 1,2,4-triazole-5-thiols with N-substituted N-chloromethyl carbamoyl chlorides. A series of thiatriazafluorenone derivatives were also prepared by reaction of benzimidazole derivatives with the same substrate. Some of the new compounds show fungicidal, herbicidal, and insecticidal activity.  相似文献   

12.
Reaction of N-aryl cyanoacetamides with hydrazine hydrate, or its monoaryl-substitution products, gives 3-arylamino-5-aminopyrazoles and 1-aryl-3-arylamino-5-aminopyrazoles. Treatment of aminopyrazoles with aryldiazonium chlorides leads to isolation of the arylazo derivatives. A hypothesis that the pyrazole derivatives synthesized have an amine structure is put forward on the basis of their chemical properties and IR spectra.  相似文献   

13.
Acylation of nitroenamine derivatives of imidazolidin-1-oxyl with carboxylic acid chlorides leads to 0-acylhydroximic acid chloride derivatives of 3-imidazolin-1-oxyl. The reaction proceeds apparently through a nitrile oxide. It was shown for the 0-benzoyl derivative that reaction of the obtained acyl chlorides with nucleophilic reagents usually gives products of chlorine atom substitution with simultaneous cleavage of the acyl group.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 2, pp. 444–450, February, 1991.  相似文献   

14.
Conclusions A method was proposed for synthesizing ketones of the barene series by the reaction of carboxylic acid chlorides with lithium derivatives of barenes.  相似文献   

15.
The synthesis of arylboronic ester derivatives from aryl chlorides by using aryl(amino)boranes is described. Palladium‐catalyzed coupling between aryl chlorides and diisopropylaminoborane leads to the formation of a C?B bond under mild conditions. A wide range of functional groups are tolerated, making this method particularly useful for the borylation of functionalized aromatics.  相似文献   

16.
Abstract

Although alkanesulfonyl chlorides react with linear imines to give rise to β-sultam derivatives, in this study, they were reacted with various cyclic imines, including 1-pyrroline, oxazoline, 5,6-dihydro-4H-oxazines and thiazines, 4,5-dihydro-3H-benzo[c]azepine, and 3,4-dihydroisoquinoline, to produce diverse products instead of β-sultam derivatives. The results indicate that alkanesulfonyl chlorides react with cyclic imines to generate N-alkanesulfonyl cyclic iminium ions, which are attacked by nucleophiles, such as water and chloride anion, in the reaction systems, affording addition products. The iminium intermediates cannot undergo a ring closure to form β-sultam derivatives. Arenesulfonyl chlorides showed similar behavior when they reacted with cyclic imines. The scope and limitation of the reaction between sulfonyl chlorides and imines were investigated.

GRAPHICAL ABSTRACT   相似文献   

17.
A room-temperature Ni-catalyzed cross-coupling of aryl, heteroaryl, and alkenyl electrophiles with aminoalkylzinc bromides, readily available from the corresponding aminoalkyl chlorides via Grignard reagents, was developed. The reaction allows a convenient one-step preparation of various aminoalkyl products, including piperidine and tropane derivatives. Such functionalized amine moieties are widely present in various biologically active molecules. Aryl, heteroaryl, and alkenyl iodides, bromides, chlorides and triflates are suitable electrophiles. A short total synthesis of two natural products, (±)-galipinine and (±)-cusparine, is also reported.  相似文献   

18.
Bartos J 《Talanta》1980,27(7):583-590
Carboxylic acids, their chlorides, anhydrides, esters, lactones, amides, lactams and imides react with hydroxylamine to give hydroxamic acids which are then treated with iron(III). Other compounds or groups of compounds can also be determined after a prior conversion into hydroxylamine-reactive derivatives. The calorimetric applications of these reactions are reviewed. The effect of various factors is discussed. A selective procedure for determination of acid chlorides and anhydrides and an improved procedure for determination of carboxylic esters and lactones are presented.  相似文献   

19.
A series of C-aroyl derivatives of 2-imidazolone and 2-benzimidazolone has been obtained by the reaction of the chlorides of the corresponding carboxylic acids with imidazolone and benzimidazolone in the presence of anhydrous aluminum chloride. A consideration of the IR spectra has shown that the substances synthesized have the lactam structure in the solid state.  相似文献   

20.
A series of new convolvine derivatives based on the alkaloid from Convolvulus subhirsutus and C. pseudocanthabrica were synthesized using alkylhalides and aliphatic and aromatic acid chlorides. Results of biological tests showed that convolvine and its derivatives exhibited pronounced antihypoxic, immunomodulating, and anti-inflammatory activity.  相似文献   

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