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1.
It was found that rhenium complex was an efficient catalyst for the acylative cleavage of C-O bond of ethers with acyl chlorides. When acyclic ethers were allowed to react with acyl chlorides in the presence of a catalytic amount of ReBr(CO)5, acylative cleavage of C-O bond of acyclic ethers smoothly proceeded to give the corresponding esters in moderate to good yields. Similarly, cyclic ethers were acylative cleaved by acyl chlorides to give the corresponding chloro substituted esters in good yields by the use of Re2O7 catalyst.  相似文献   

2.
Bo Wang  Jie Tang 《Tetrahedron》2009,65(27):5409-5412
Highly efficient synthesis of capsaicin analogues was developed using condensation of vanillylamine with acyl chlorides in a biphase H2O/CHCl3 system under mild conditions. For C4-C18 aliphatic or aromatic acyl chlorides, the yields were up to 93-96% with high purity after a simple work-up procedure, and only 1-1.16 equiv of acyl chloride was needed in the reaction.  相似文献   

3.
Aromatic ketones are synthesized efficiently via palladium-catalyzed cross-coupling reaction of boronic acids with acyl chlorides in the presence of K3PO4 hydrate in toluene. This allows the use of aliphatic acyl chlorides as the starting material. Hydrated water plays a significant role as an H2O source to activate the catalytic system.  相似文献   

4.
Acid chlorides react with SmI2 to give α-diketones. Various experiments show that the initially formed acyl radical is rapidly transformed into an acyl anion which is thus generated by quite an unusual route.This species acylates acid chlorides, aldehydes and ketones in situ to give α-diketones and α-ketols. There are some limitations to this acyl anion chemistry but the reactions are realized with a good efficiency at room temperature in THF solution.  相似文献   

5.
Azobenzene compounds without big substituents were conveniently reduced by a system consisting of SmI2/THF and successively reacted smoothly with analogous aliphatic acyl chlorides or acid anhydrides to afford corresponding mono‐acyl symmetrical hydrazobenzene under mild and neutral conditions in one pot; while other azo compounds reacted under similar conditions, amides were the terminate products.  相似文献   

6.
While many carboxylic acids could be converted directly to acyl fluorides by using BrF3, the reaction with acyl chlorides was found to be of a more general nature and yields better results. Surprisingly, reacting t-butyl esters with bromine trifluoride also resulted in acyl fluorides in reasonable yields. The reactions were completed in a few seconds at 0 °C.  相似文献   

7.
The potential energy surface for reactions of acyl iodides and acyl chlorides with methanol was studied by quantum-chemical methods. Stereoelectronic parameters of the prereaction bimolecular complexes and possible reaction products were examined. Transition states were localized for the transformation of prereaction complexes into final products. Dual reactivity of acyl iodides toward methanol was explained in terms of similar activation parameters found for the four-center and SN2 reaction mechanisms.  相似文献   

8.
Unsymmetrical α -diketones have been obtained via cross coupling of acyltins with acyl halides under PdCl2(PPh3)2 catalysis while symmetrical α -diketones have been readily obtained via “in situ” formation of acyltins using hexabutylditin and acyl chlorides under similar experimental conditions.  相似文献   

9.
The Sm/cat. CoCl2 system promoted diselenides to react with anhydrides or acyl chlorides to afford selenoesters in good yield under mild and neutral conditions.  相似文献   

10.
The reaction of SF5OOH with acyl fluorides in the presence of NaF has been investigated and found to yield new peroxy esters of the type RC(O)OOSF5. An alternate method of synthesis using SF5OOCl and acyl chlorides is discussed and the cesium fluoride catalyzed conversion of two of the esters to RCF(OF)OOSF5 is described.  相似文献   

11.
Alkyl and acyl derivatives of 3,4-dihydropyrimidin-2(1H)-thiones were synthesized in good to excellent yields in the presence of Cs2CO3, a mild base. The method evidences a selective S-alkylation when using acyl chlorides as efficient acylating agents at room temperature on the 2-thioxo-dihydropyrimidone moiety. A possible mechanistic interpretation of the different selectivities in case of alkylation and acylation was done with the help of a geometry optimization process.  相似文献   

12.
A palladium‐catalyzed, norbornene‐mediated Catellani ortho‐acylation reaction was developed by the use of either acyl chlorides or acid anhydrides as acylation reagents. The addition of more than a stoichiometric amount of H2O is crucial for this transformation when acid chlorides are used, and kinetic studies indicate that the active acylation reagent is possibly an acid anhydride.  相似文献   

13.
The influence of catalysts, acid chlorides, and solvents on the acylation of methyl 2-methyl-4H-thieno[3,2-b]pyrrole-5-carboxylate was studied. The use of AlCl3 allows the regioselective introduction of the acyl group into position 3 to be performed, whereas the acyl group is regioselectively introduced into position 6 of thienopyrrole when SnCl4 is used.  相似文献   

14.
A highly-efficient and practical method for the formation of ynones from a variety of acyl chlorides and terminal alkynes catalyzed by a nanosized MCM-41 anchored palladium bipyridyl complex is described herein. Aroyl, heteroaroyl, and alkyl acyl chlorides were easily coupled with terminal alkynes, giving good to high isolated yields in the presence of a very low catalyst loading (0.002-0.1 mol % Pd) in Et3N or diisopropylethylamine at 50 °C. Furthermore, the reaction scale was up to 150 mmol for a single batch reaction, providing the potential for practically synthetic application. After centrifugation, the supported catalyst was able to be recycled and reused several times with only a slight decrease in activity.  相似文献   

15.
Montmorillonite K-10 clay supported InCl3 is a highly active catalyst for the acylation of aromatic alcohols and phenols with different acyl chlorides. This catalyst can be reused in reactions a number of times without very significant loss of catalytic activity  相似文献   

16.
Benzylzirconocene intermediate, which was readily prepared by a reaction of o-alkoxymethylstyrene with `Cp2Zr' under mild conditions, reacted with acyl chlorides in the presence of a catalytic amount of CuBr-SMe2 to give ketone derivatives in moderate to good yields.  相似文献   

17.
Azo compounds were conveniently reduced by a system consisting of Sm/TiCl4 to produce aniline anions. This anion species reacted smoothly with aliphatic acyl chlorides or acid anhydrides to afford corresponding amides under mild and neutral conditions.  相似文献   

18.
The reaction of acyl chlorides with cyclic five-membered β-enaminoesters gave exclusively N-acylated products while reaction of acyl chlorides with cyclic seven-membered β-enaminoesters gave only C-acylated products. In the case of cyclic six-membered β-enaminoesters, the reaction of acyl chlorides gave a mixture of N-acylated and C-acylated products.  相似文献   

19.
Aromatic ketones were synthesized via a palladium catalyzed cross-coupling reaction of boronic acids with acyl chlorides in the presence of Na2CO3 at room temperature under solvent-free conditions. The ligand-free and mild reaction conditions, highly rapid reaction rate and good to excellent yields are important features of this method.  相似文献   

20.
Reaction of acetylacetone with acyl chlorides in the presence of SmI3 gave β-diketones RCOCH2COCH3 (I) or RCOCH2COR (II) in good yields under mild and neutral conditions.  相似文献   

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