Acylation Of Amines Research Articles

ChemInform Abstract: Selective Mono‐ and Di‐N‐alkylation of Aromatic Amines with Alcohols and Acylation of Aromatic Amines Using Ph3P/DDQ.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Iron-Catalyzed Inexpensive and Practical Synthesis of N-Substituted Pyrroles in Water

An operationally simple, practical, and economical protocol for iron(III) chloride catalyzed Paal-Knorr pyrrole synthesis in water in good to excellent yields has been developed. Several N-substituted pyrroles are readily prepared from the reaction of 2,5-dimethoxytetrahydrofuran and aryl/alkyl, sulfonyl and acyl amines under very mild reaction conditions.

Templated Synthesis of Peptide Nucleic Acids via Sequence-Selective Base-Filling Reactions

The templated synthesis of nucleic acids has previously been achieved through the backbone ligation of preformed nucleotide monomers or oligomers. In contrast, here we demonstrate templated nucleic acid synthesis using a base-filling approach in which individual bases are added to abasic sites of a peptide nucleic acid (PNA). Because nucleobase substrates in this approach are not self-reactive, a base-filling approach may reduce the formation of nontemplated reaction products. Using either reductive amination or amine acylation chemistries, we observed efficient and selective addition of each of the four nucleobases to an abasic site in the middle of the PNA strand. We also describe the addition of single nucleobases to the end of a PNA strand through base filling, as well as the tandem addition of two bases to the middle of the PNA strand. These findings represent an experimental foundation for nonenzymatic information transfer through base filling.

Mild and Efficient Cooper (II) Oxide-Catalyzed Acylation of Amines and Alcohols

Therefore, the development of a mild and efficient method for the synthesis of amide bonds in the absence of a base is strongly desired. In this communication, we report on a new and efficient method for the synthesis of amides from corres-ponding acyl chlorides and amines using a catalytic amount of cooper (II) oxide (CuO). To the best of our knowledge, this is the first demonstration of CuO-catalyzed acylation of amines and alcohols.Initially, we chose benzoyl chloride and cyclohexylamine as model compounds. When benzoyl chloride was treated with cyclohexylamine (1 equiv) and CuO (1 equiv) in CH

Mild and Useful Method for N-Acylation of Amines

Iodine is found to promote quantitative N-acylation of primary and secondary amines (aliphatic and aromatic) in a very short time with an equimolar amount of acetyl chloride and benzoyl chloride under solvent-free conditions at room temperature. This catalytic acylation of amines offers an additional useful method for the acetylation using acetyl chloride instead of acetic anhydride and other acetylating agents. This method is also useful in the N-acylation of heterocycles. Mild reaction condition, high selectivity, efficiency, and good yields are some of the major advantages of the procedure.

Acylation and oxidation of primary amines and alcohols catalyzed by nanoporous polyaniline emeraldine salt

We described the convenient and efficient catalytic acylation and oxidation of primary amines and alcohols compounds into amide/ester or aldehyde compounds using nanoporous polyaniline emeraldine salts catalysts. The reaction mechanism of acylation by polyaniline emeraldine salt catalyst is explained by acid catalyzed addition–elimination reaction, whereas oxidation process is proposed to occur through a radical pathway.

Zirconocene bis(perfluorooctanesulfonate)s-catalyzed acylation of alcohols, phenols, thiols, and amines under solvent-free conditions

Air-stable zirconocene bis(perfluorooctanesulfonate)s [Cp2Zr(OPf)2, OPf = OSO2C8F17] showing high Lewis acidity and high thermal stability was prepared by reacting Cp2ZrCl2 with AgOPf, and examined as a catalyst for acylation reactions. It was found that in the acetylation of various alcohols, phenols, thiols, and amines by equimolar of acetic anhydride, Cp2Zr(OPf)2 exhibits high activity and selectivity to desired products under mild and solvent-free conditions. In the acylation of 2-phenylethanol across various acylating reagents, it also shows good catalytic efficiency. In a test of ten cycles, Cp2Zr(OPf)2 shows little loss of activity. The results afford a general and efficient method for the acylation of alcohols, phenols, thiols, and amines using zirconium bis(perfluorooctanesulfonate) as catalyst.

Traceless Solid-Phase Synthesis of Heteroannulated 1,3-Oxazin-6-ones

A microwave-assisted solid-phase synthesis of heteroannulated 1,3-oxazin-6-ones has been developed. Significant rate enhancement was observed for all steps carried out under microwave irradiation, and the overall reaction time was dramatically shortened when compared to the conventional procedures. A representative set of 20 bi- and tricyclic heteroannulated 1,3-oxazin-6-ones was prepared. Key steps in the synthesis are (i) five-member heterocycle formation, (ii) acylation of amine, and (iii) ring closure to give the heteroannulated 1,3-oxazin-6-one.

Selective mono- and di-N-alkylation of aromatic amines with alcohols and acylation of aromatic amines using Ph 3P/DDQ

Selective N-monoalkylation of aromatic amines with 1° and 2° alcohols and conversion of aromatic amines to amides are performed immediately and in excellent yields using triphenylphosphine (PPh 3) and 2,3-dichloro-5,6-dicyanobenzoquinone (DDQ) in dichloromethane at room temperature. Symmetrical and unsymmetrical N,N-dialkylation of aromatic amines are also carried out in modest yield at room temperature by this reagent system.

ChemInform Abstract: New, Efficient, Selective, and One‐Pot Method for Acylation of Amines.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Highly efficient chemoselective N-acylation with water microreaction system in the absence of catalyst

A high-speed, highly efficient chemoselective N-acylation by anhydride was achieved in the absence of catalyst for exothermic (DeltaH>0) and endothermic (DeltaH<0) acylation of various amines and anilines with the microreaction system of ambient water (micro-onH2O) and subcritical water (micro-subH2O), where the desired N-acylated products are chemoselectively obtained with high yield(s) and excellent selectivity (>95%).

Chemoselective acylation of amines, thiols and phenols using 2,4,6-triacyloxy-1,3,5-triazine (TAT) as a new and effective reagent under mild condition

A facile chemoselective acylation of amines, thiols and phenols using 2,4,6-triacyloxy-l,3,5-triazine (TAT) under mild condition is described. New reagent, high product yield, short reaction time, ease of operation and solvent free reaction condition is the most acceptable feature of the present method.

Polyaniline nanofiber supported FeCl 3: An efficient and reusable heterogeneous catalyst for the acylation of alcohols and amines with acetic acid

An efficient and reusable polyaniline nanofiber supported ferric chloride catalyst was developed and characterized by FT-IR, UV–vis, XPS, TEM and XRD techniques. The catalyst was used in the selective acylation of alcohols and amines employing acetic acid as an acylating agent to obtain the corresponding acetates and acetamides in good to excellent yields.

A Practical and Efficient Approach to PNA Monomers Compatible with Fmoc‐Mediated Solid‐Phase Synthesis Protocols

AbstractA straightforward synthesis of orthogonally protected PNA monomers is described. Protected aminoethylglycine (Aeg) monomers were efficiently prepared by reductive amination of N‐Fmoc‐glycinaldehyde with glycine methyl ester and the subsequent acylation of the free amine with N‐bis‐Boc‐protected nucleobase acetic acids. The exocyclic amine group of the nucleobases, including the notoriously difficult‐to‐protect guanine nucleobase, was protected with a bis‐Boc carbamate group; this increased the solubility of the nucleobases in the most common organic solvents. The current protocol allows all Aeg monomers to be prepared on both the micro‐ and macroscale, which avoids or minimizes the use of toxic reagents or solvents, and moreover, cheap starting materials are used. (© Wiley‐VCH Verlag GmbH &amp; Co. KGaA, 69451 Weinheim, Germany, 2008)

Highly efficient heterogenous catalyst for acylation of alcohols and amines using natural ferrous chamosite

An efficient acylation of alcohols and amines employing carboxylic acid as an acylating agent using ferrous chamosite-natural marine clay as the heterogeneous and reusable catalyst has been realized for the first time, through the tuning of the reaction by simple exposure of the reactants to conventional heating or ultrasound irradiation in the absence of any additive under ligand and solvent free conditions.

Analysis and Removal of Organic Pollutants in Biologically Treated Landfill Leachate by an Inorganic Flocculent Composite of Al(III)‐Mg(II)

A novel inorganic flocculent composite of Al(III)-Mg(II) poly-magnesium-aluminum-sulfate (PMAS) is used to remove organic matter from biologically treated leachate in some landfills in Beijing, China. Jar-test experiments are employed to determine the optimum conditions for the removal of organic matter, which is represented as UV(254). Under optimum conditions, the removal of COD, BOD(5), and color is also determined. Moreover, gas chromatography coupled with mass spectrometry (GC-MS) is used to analyze the organic matter in the biologically treated leachate before and after treatment by the coagulant. The experimental results indicate that the removal of COD, BOD(5), UV(254), and color by coagulation with PMAS can reach above 65%, 60%, 85%, and 85%, respectively, under optimal conditions. This greatly weakens its pollution extent and improves its visual appeal. Forty-one kinds of organic pollutants in the biologically treated leachate were determined. Some of them belong to the Black List of water environmental preferred controlled pollutants, as judged by the United States and China. The species of alkyl, alkene, acyclic alcohol, and acyclic acyl amines are about 85% removed, some of them are removed completely, while the species of acids, esters, and ketones are removed at about 65%. Those contaminants with benzene rings, such as aromatic hydrocarbons, hydroxybenzene, aromatic alcohol, and aromatic acyl amine, are about 50% partially removed.

Color and organic compounds removal from secondary effluent of landfill leachate with a novel inorganic polymer coagulant

Emerging contaminants in landfill leachate are causing environmental concerns due to their adverse impacts on the aquatic environment. The most popular biological process is mostly the first stage in combination with additional physical-chemical process. Current post-treatments are limited by high operating costs, low treatment efficiencies, or sensitive operating conditions. Poly-aluminium(III)-magnesium(II)-sulfate (PMAS in brief) is used to remove color and organic compounds in secondary effluent of landfill leachate. More than 40 kinds of organic matters in the secondary effluent are identified and 10 of them belong to the Black List of environmental preferred controlled pollutants considered by EPA of USA or China. Removals of COD, BOD(5), UV(254) and color by coagulation with PAMS can reach above 60%, 55%, 85% and 85% respectively under the optimum conditions. The species of alkyl, alkene, acyclic alcohol and acyclic acyl amine are efficiently removed (about 85%), with some of them removed completely, while the species of acid, ester and ketone are mostly removed (about 65%) and such matters with benzene ring as aromatic hydrocarbon, hydroxybenzene, aromatic alcohol, aromatic acyl amine are partially removed (about 50%). Organic pollutants in the secondary effluent are greatly removed with high efficiency here, which greatly weakens its pollution extent.

Single‐Crystalline Molecular Flasks: Chemical Transformation with Bulky Reagents in the Pores of Porous Coordination Networks

1The pore channels facilitate increased mobility and rapid diffusion of included guest molecules. Large organic molecules can readily enter into the pores via guest exchange. In this sense, the pore interior is a pseudo-solution state where chemical reactions may proceed as in a solution, yet can be directly analyzed by crystallography. Here, we show that single-crystal-tosingle-crystal chemical reactions with large, common reagents proceed quite smoothly inside the pores of the network. Taking advantage of the network’s robust crystallinity, we succeeded in the acylation and ureidation of aromatic amines and imine formation from aromatic aldehydes within a single crystal. The pores of the network complexes thus serve as “single crystalline molecular flasks”. 2 In related studies, we have reported the preliminary results of the diffusion of aldehydes into the pores of porous networks to form imine. 3

Preparation of Morpholine-2-one and 1,4-Oxazepan-2-one Derivatives by Cyclization Reaction between N-Bts Amino Alcohol and Chloroacetyl Chloride

Sulfonamide is one of the most stable nitrogen protective group, and various sulfonamides have been developed and applied for organic synthesis. However, deprotection of most sulfonamides has drawbacks due to harsh reaction conditions. Benzothiazole-2-sulfonyl (Bts) was first reported as an amine protective group in amino acid synthesis. Compared to other sulfonyl groups, Bts is an attractive choice because it requires milder deprotection conditions. Initially, Bts chloride, the reagent for Bts protection for simple amines, was prepared using Cl2 gas, which is toxic and inconvenient. Recently, an improved methodology using aqueous sodium hypochlorite instead of toxic Cl2 was reported and making Bts protection much easier. The Bts group is known to have an electron withdrawing property, and Bts protected amide shows a different reactivity compared to other N-protected amide derivatives. Although usual amide bond is strong enough not to be easily hydrolyzed or aminolized, N-Bts amide linkage can be broken by attack of simple amine nucleophiles. This is another benefit of Bts protection, and the ring opening reaction of 1-Bts piperazin-2-one derivative as a peptide nucleic acid (PNA) monomer with a PNA oligomer anchored on solid phase has been usefully applied for solid phase PNA synthesis. In this paper, a facile cyclization reaction of N-Bts amino alcohol with chloroacetyl chloride is described. We speculated that if the Bts group could effectively withdraw electrons from nitrogen, nucleophilicity of Bts attached amine would be reduced, and a different reactivity toward electrophiles would be observed compared to normal amine derivatives. These subtle reactivity differences could be an effective means of obtaining different regioselectivity. Detailed data pertaining to change of nucleophilicity due to Bts protection has not been reported thus far. To investigate this hypothesis, Bts, Ts (toluensulfonyl), and Boc (t-butyl carbamate) protected amino alcohols were prepared, and reactions with chloroacetyl chloride were performed (Scheme 1). Between two chlorides in chloroacetyl chloride, acyl chloride is known to be more reactive toward usual nucleophiles. In the case of unprotected amino alcohol, the amine should react with acyl chloride prior to OH, and OH can subsequently attack α-carbon to produce a morpholine-3-one. However, for N-protected amino alcohol, OH should be acylated prior to the acylation of Nprotected amine. If the N-protected amine has sufficient reactivity to perform intramolecular cyclization to attack αcarbon, a morpholine-2-one derivative can be prepared. In the reaction of N-Bts amino alcohol (2a, b), The OH group reacted with acyl chloride to form ester 3a, b. After workup to remove remaining chloroacetyl chloride, and stirring in DMF with K2CO3, it was found that N-Bts amine could substitute a chloride at α-carbon, and morpholine-2one (4a) or 1,4-oxazepan-2-one (4b) derivative was produced. When N-Ts amino ethanol (5a) was reacted with chloroacetyl chloride dropwise, a different outcome was obtained. A mixture of O-acylated (6a) and diacylated compound 8 was produced in 1:4 ratios. The production of diacylated compound 8 as a major product means that N-Ts amine has enough nucleophilicity to react with acyl chloride, and its reactivity is higher than N-Bts amine. When O-acylated product (6a) was separated and stirred with K2CO3, morpholine-2-one derivative (7a) was obtained.

New, Efficient, Selective, and One-Pot Method for Acylation of Amines

Hydrazine hydrate with acetic and propionic acids was an efficient reagent for acylation of primary and secondary amines at reflux temperatures. The reported one-pot method is high-yielding, simple, mild, and inexpensive.