共查询到20条相似文献,搜索用时 390 毫秒
1.
Madabhushi Sridhar Mallu Kishore Kumar ReddyVangipuram Venkata Sairam Jillella RaveendraKondal Reddy Godala Chinthala NarsaiahBeeram China Ramanaiah Cirandur Suresh Reddy 《Tetrahedron letters》2012,53(27):3421-3424
An efficient method for the preparation of nitriles directly from aldehydes by reaction with AHA using Bi(OTf)3 as the catalyst is described. Bi(OTf)3 is shown to be an efficient catalyst also for the conversion of aldoximes into nitriles. 相似文献
2.
Mohammad Navid Soltani Rad Ali Khalafi-Nezhad Mohammad Ali Faghihi 《Tetrahedron letters》2007,48(38):6779-6784
A convenient and efficient one-pot preparation of nitriles from alcohols using N-(p-toluenesulfonyl)imidazole (TsIm) is described. In this method, treatment of alcohols with a mixture of NaCN, TsIm and triethylamine in the presence of catalytic amounts of tetra-n-butylammonium iodide (TBAI) in refluxing DMF furnishes the corresponding alkyl nitriles in good yields. This methodology is highly efficient for various structurally diverse alcohols with selectivity for ROH: 1° > 2° > 3°. 相似文献
3.
Árpád Kiss 《合成通讯》2013,43(13):1778-1786
A simple heterogeneous metal-catalyzed method was developed for the transformation of aldoximes into nitriles. Molecular sieve (4 Å) modified with copper(II) proved to be an efficient catalyst for the conversion. Supplemental materials are available for this article. Go to the publisher's online edition of Synthetic Communications® to view the free supplemental file. 相似文献
4.
Mohammad Navid Soltani Rad Ali Khalafi-Nezhad Somayeh Behrouz Zohreh Amini Marzieh Behrouz 《Phosphorus, sulfur, and silicon and the related elements》2013,188(8):1658-1671
A facile and highly efficient method for one-pot Beckmann rearrangement of ketoximes into N-substituted amides using N-(p-toluenesulfonyl)imidazole (TsIm) is described. In this method, ketoximes are refluxed with TsIm and Cs2CO3 in the presence of SiO2 as a recyclable catalyst in DMF affording the corresponding amides in high yields. This methodology is highly efficient and regioselective for various structurally diverse ketoximes including symmetrical and unsymmetrical as well as cyclic oximes. The results of quantum mechanical studies used to rationalize the experimental outcomes are discussed. 相似文献
5.
Eng‐Chi Wang Keng‐Shiang Huang Hsing‐Ming Chen Chung‐Chin Wu Gwo‐Jiun Lin 《中国化学会会志》2004,51(3):619-627
A new and highly efficient method for the conversion of aldoximes to nitriles was established. By fusing with phthalic anhydride, aldoximes were efficiently and smoothly converted into nitriles, in high yields (over 85%) and in a short time (within 5 minutes). The mixture of phthalic anhydride, a cyclic anhydride, and aldoximes in fusing state set up an ideal transition state for a selective [3.3]‐sigmatropic rearrangement of the acylated aldoximes to nitriles. 相似文献
6.
Mohammad Navid Soltani Rad Somayeh Behrouz Abdo-Reza Nekoei 《Phosphorus, sulfur, and silicon and the related elements》2013,188(4):465-476
Abstract A facile and efficient method for one-pot synthesis of N-alkyl sulfonamides from alcohols using N-(p-toluenesulfonyl)imidazole (TsIm) is described. In this protocol, treatment of various potassium sulfonylamide salts and alcohols in the presence of TsIm and triethylamine in refluxing DMF furnishes the corresponding N-alkyl sulfonamides in good to excellent yields. This methodology is highly efficient for reaction of various structurally diverse primary and secondary alcohols as well as potassium sulfonylamides. Also, the density functional theoretical calculations are employed to mechanistically study this protocol. [Supplementary materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements for the following free supplemental files: Additional text and figures.] 相似文献
7.
《合成通讯》2013,43(16):2535-2541
ABSTRACT Primary amides and aldoximes are easily converted to their corresponding nitriles using a mixture of triphenylphosphine and N-chlorosuccinimide in dichloromethane at room temperature. The reaction of aldoximes occurs almost immediately and primary amides in 0.5?h by this method. By this procedure secondary amides are produced by Beckmann rearrangement of ketoximes. 相似文献
8.
The reaction of a variety of aldoximes with perfluoroalkanosulfonyl fluoride in the presence of 1,8-diazabicyclo[5.4.0]undec-7-ene(DBU) in dichloromethane smoothly generated the corresponding nitriles in 70%–95% yields. 相似文献
9.
A simple one-pot procedure for the direct conversion of alcohols into azides using TsIm 总被引:1,自引:0,他引:1
A facile and efficient method for one-pot conversion of alcohols into azides using N-(p-toluenesulfonyl)imidazole (TsIm) is described. In this method, alcohols are refluxed with a mixture of NaN3, TsIm and triethylamine in the presence of catalytic amounts of tetra-n-butylammonium iodide (TBAI) in DMF affording the corresponding alkyl azides in good yields. This methodology is highly efficient for various structurally diverse alcohols with selectivity for ROH: 1° > 2° > 3°. 相似文献
10.
Mohammad Navid Soltani Rad Ali Khalafi-Nezhad Mohammad Ali Faghihi Abolfath Parhami 《Tetrahedron》2008,64(8):1778-1785
A convenient and efficient one-pot N-alkylation of nucleobases from alcohols using N-(p-toluenesulfonyl)imidazole (TsIm) is described. In this method, treatment of alcohols with a mixture of purine or pyrimidine nucleobase, TsIm, K2CO3, and triethylamine in refluxing DMF regioselectively furnishes the corresponding N-alkyl nucleobases in good yields. This methodology is highly efficient for various structurally diverse primary alcohols. 相似文献
11.
A green and suitable protocol for the conversion of aldoximes into nitriles is described. The transformation is carried out under solvent-free conditions using FeCl3-silica medium. The protocol offers a green, single-step facile procedure with the use of less toxic metal salt to isolate nitriles in good to excellent yields. 相似文献
12.
Debasree Saha 《Tetrahedron letters》2009,50(44):6088-5187
A simple and convenient procedure for the synthesis of nitriles by dehydration of aldoximes using an ionic liquid, 1-pentyl-3-methylimidazolium tetrafluoroborate, [pmim]BF4 under organic solvent-free condition, has been developed. A variety of aromatic, heteroaromatic and aliphatic aldoximes are converted to the corresponding nitriles. The ionic liquid is recovered and reused for subsequent reactions. 相似文献
13.
A simple and convenient procedure for the synthesis of nitriles by dehydration of aldoximes using a PCC (pyridiniumchlorochromate) has been developed. A variety of aromatic, heteroaromatic, and aliphatic aldoximes are converted.
Supplementary materials are available for this article. Go to the publisher's online edition of Synthetic Communications® for the full spectral details. 相似文献
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Mohammad Navid Soltani Rad Somayeh Behrouz Ali Khalafi-Nezhad 《Tetrahedron letters》2008,49(7):1115-1120
An efficient and selective method for esterification of alcohols using N-(p-toluenesulfonyl)imidazole (TsIm) is described. In this method, alcohols are refluxed with a mixture of RCO2Na (R: alkyl and aryl), TsIm, and triethylamine in the presence of catalytic amounts of tetra-n-butylammonium iodide (TBAI) in DMF to afford the corresponding esters in good yields. This methodology is highly efficient for various structurally diverse alcohols with selectivity for ROH: 1° > 2° > 3°. 相似文献
18.
《Angewandte Chemie (International ed. in English)》2017,56(40):12361-12366
A cyanide‐free platform technology for the synthesis of chiral nitriles by biocatalytic enantioselective dehydration of a wide range of aldoximes is reported. The nitriles were obtained with high enantiomeric excess of >90 % ee (and up to 99 % ee ) in many cases, and a “privileged substrate structure” with respect to high enantioselectivity was identified. Furthermore, a surprising phenomenon was observed for the enantiospecificity that is usually not observed in enzyme catalysis. Depending on whether the E or Z isomer of the racemic aldoxime substrate was employed, one or the other enantiomer of the corresponding nitrile was formed preferentially with the same enzyme. 相似文献
19.
Silylated derivatives of oximes are important intermediates in organic synthesis, and have found application in the preparation of various nitrogen containing compounds including nitriles, amines, nitrones, and hydroxylamines. An efficient method for the O-silylation of aldoximes and ketoximes through a platinum-catalyzed reaction using trisubstituted-hydrosilanes is described. The reaction works well with a range of aliphatic and aromatic oximes when using triethylsilane as a silylating agent. Furthermore, a number of tri-substituted organosilanes including triisopropylsilane, diethoxymethylsilane, triphenylsilane, and triethoxysilane were also explored. 相似文献
20.
An operationally simple and high yielding procedure has been developed for the preparation of nitriles from aldoximes and primary amides using bromodimethylsulfonium bromide (BDMS) as a novel and efficient reagent in the absence of any added base or catalyst. The optimal protocol is applicable to access a wide range of cyano compounds including aromatic, heterocyclic, and aliphatic species. The conversion of aldoximes to nitriles takes place at room temperature in acetonitrile, whereas acetonitrile at reflux temperature is required for rapid conversion in the case of primary amides. 相似文献