Addition Of Primary Amines Research Articles

Two‐Step Synthesis of Multifunctional γ‐Lactams from γ‐Lactone

We present herein an efficient and rapid method for the synthesis of N,1‐dialkyl‐4‐(2‐hydroxyethyl)‐5‐oxopyrrolidine‐3‐carboxamides based on the conversion of γ‐lactone to γ‐lactam via the conjugate addition of primary amines to an ethyl α‐functionalized acrylate followed by intramolecular cyclization.

Aza-Michael Addition of Primary Amines by Lipases and Microwave Irradiation: A Green Protocol for the Synthesis of Propanenitrile Derivatives

aza-Michael Addition of Primary Amines by Lipases and Microwave Irradiation: A Green Protocol for the Synthesis of Propanenitrile Derivatives

Understanding α,β-Unsaturated Imine Formation from Amine Additions to α,β-Unsaturated Aldehydes and Ketones: An Analytical and Theoretical Investigation

A combination of in situ IR spectroscopy (ReactIR) and DFT calculations have been used to understand what factors govern the selectivity in the addition of primary amines to α,β-unsaturated aldehydes and ketones, i.e., 1,2- versus 1,4-addition. It has been found that the 1,2-addition products (α,β-unsaturated imines following addition and elimination) usually predominate for most systems. However, exceptions, such as methyl vinyl ketone, selectively give 1,4-addition products. This has been rationalized by DFT calculations that show that major conformational effects are involved, controlled mainly by steric effects of carbonyl substituents, resulting in a model that provides simple and predictable preparation of α,β-unsaturated imines for in situ utilization in synthesis.

ChemInform Abstract: Four‐Component Synthesis of Disubstituted 1,3,4‐Oxadiazoles from N‐Isocyaniminotriphenylphosphorane, Phenylacetylenecarboxylic Acid, Chloroacetone Derivatives, and Primary Amines.

Abstract The 1:1 imine intermediate generated by the addition of primary amine to chloroacetone derivatives is trapped by N-isocyaniminotriphenylphosphorane in the presence of phenylacetylenecarboxylic acid, leading to the formation of the corresponding iminophosphorane intermediate. Disubstituted 1,3,4-oxadiazole derivatives are formed via intramolecular aza-Wittig reaction of the iminophosphorane intermediate. The reactions were completed in neutral conditions at room temperature. The disubstituted 1,3,4-oxadiazole derivatives were prepared in excellent yields. Supplemental materials are available for this article. Go to the publisher's online edition of Synthetic Communications® to view the free supplemental file.

ChemInform Abstract: Regioselective Reduction of 1H‐Pyrrole‐2,3‐diones with Thioacetamide.

AbstractThioacetamide acts as a regioselective reducing agent by melting together with (I).

Water-Soluble Cruciforms and Distyrylbenzenes: Synthesis, Characterization, and pH-Dependent Amine-Sensing Properties

Three water-soluble fluorescent aldehyde-substituted distyrylbenzene derivatives were prepared using Heck or Horner methodologies. Water solubility was achieved through the addition of branched oligoethylene glycol side chains; these are attached via an ether bridge to the aromatic nucleus. The aldehydes are almost nonfluorescent in water, but addition of primary amines turns the fluorescence on; formation of imines results. Control of the basicity of the media allows further discrimination of the analytes employed. 1,3-Diaminopropane reacts with these aldehydes. Instead of an imine, a brightly fluorescent aminal forms. Amino acids are almost always nonreactive toward these aldehydes. Exceptions are lysine and cysteine, which form an imine and a thioaminal, respectively, discreating the aldehyde unit under fluorescence turn-on in water. The detection limit and time of completion of the sensing event were evaluated. Dialdehydes 3 and 16 were comparable on both counts. The cross-shaped 16 did react approximately twice as quickly with 1,3-diaminopropane.

Regioselective reduction of 1H-pyrrole-2,3-diones with thioacetamide

The addition of primary amines to carbon atoms in the positions 2 and 5 of 1-aryl-4-aroyl-5-methoxycarbonyl-1Нpyrrole-2,3-diones is described [1, 2]; the reactions of these pyrrolediones with amides and thioamides are not studied. On melting 1-aryl-4-benzoyl-5-methoxycarbonyl-1Нpyrrole-2,3-diones Ia, Ib with thioacetamide (II) we obtained 1-aryl-4-benzoyl-3-hydroxy-5-methoxycarbonyl2,5-dihydro-1Н-pyrrol-2-ones IIIа, IIIb. The spectral characteristics of compounds IIIа, IIIb are very similar to those of the known substituted 3-hydroxy-2,5-dihydro-1Н-pyrrol-2-ones [2].

Four-Component Synthesis of Disubstituted 1,3,4-Oxadiazoles from N-Isocyaniminotriphenylphosphorane, Phenylacetylenecarboxylic Acid, Chloroacetone Derivatives, and Primary Amines

The 1:1 imine intermediate generated by the addition of primary amine to chloroacetone derivatives is trapped by N-isocyaniminotriphenylphosphorane in the presence of phenylacetylenecarboxylic acid, leading to the formation of the corresponding iminophosphorane intermediate. Disubstituted 1,3,4-oxadiazole derivatives are formed via intramolecular aza-Wittig reaction of the iminophosphorane intermediate. The reactions were completed in neutral conditions at room temperature. The disubstituted 1,3,4-oxadiazole derivatives were prepared in excellent yields. Supplemental materials are available for this article. Go to the publisher's online edition of Synthetic Communications® to view the free supplemental file.

Non-isocyanate polyurethanes: from chemistry to applications

Conventional polyurethanes involve the use of isocyanates, which require hazardous and toxic phosgene for their manufacture. These monomers cannot be manufactured without elaborate safety devices and huge investment. Isocyanates are also considerably toxic and moisture sensitive. Growing global awareness of the need to protect our environment and continually strive to ensure the safety, health and well-being of those in the industry and consumers has created a demand for environment-friendly products. The cyclic carbonate–primary amine addition reaction which results in hydroxyurethanes is a unique reaction and has been extensively studied over the last few years. This chemistry is now attracting research interest due to its potential application in the preparation of “green”, non-porous, moisture-insensitive, isocyanate free polyurethanes. This review focuses on catalysis, the mechanism involved in the formation of Non-Isocyanate Polyurethanes (NIPU) from five-membered cyclic carbonates and the reaction kinetics for their synthesis. The higher homologues of the cyclic carbonate family, the six-membered cyclic carbonates, are similar to, but more reactive than, the five-membered cyclic carbonates and can also serve as a source for production of isocyanate free polyurethanes. This review also summarizes various application of NIPU in coatings, composites, construction and biochemical fields.

Highly diastereoselective synthesis of N-substituted 4-(diethoxyphosphoryl)-pyrrolidines-3-carboxylate starting from tetraethyl methylenediphosphonate

 This paper describes a convenient synthesis of novel series of 3,4-disubstituted pyrrolidines based on the aza-Michael addition of primary amines to 3,4-difunctionalized-1,3-diene followed by an intramolecular cyclization.

Palladium complexes derived from N,N-bidentate NH-iminophosphorane ligands: synthesis and use as catalysts in the Sonogashira reaction

The addition of primary amines to the C=C bond of diphenylalkenyl iminophosphoranes yielded a new subtype of N,N-bidentate ligands bearing N=P(V)-C-C-NH backbones. These donor ligands reacted with PdCl(2)(COD) to give the corresponding σN,σN-palladium complexes containing secondary amino groups, bearing an intrinsically chiral nitrogen atom, and iminophosphorane units. These new complexes have been fully characterized by the use of spectroscopic techniques and X-ray crystallography. The comparison of the data extracted from their solution NMR spectra with their solid state structures demonstrated the conformational stability of their six-membered chelate ring and also the configurational stability of the chiral nitrogen atom, thus ruling out an arm-off racemization process. The addition of the chiral, racemic α-methylbenzylamine to the prochiral P-alkenyl iminophosphoranes yielded mixtures of the two expected diasteroisomeric ligands in low diastereoisomeric ratios. One of these mixtures was resolved into their components, each one in turn giving rise to a pair of diasteromeric palladium complexes epimeric at the amino nitrogen atom. One selected example of the new complexes efficiently catalyzes the copper- and amine-free Sonogashira reaction of aryl halides with acetylenes.

The reaction of dialkyl acetylenedicarboxylates with 2-oxo-2-phenylacetaldehyde in the presence of primary amines: synthesis of alkyl 2-benzoyl-4-alkylamino-5-oxo-2,5-dihydro-3-furan carboxylate derivatives

A 3-component domino reaction approach between a primary amine, a dialkyl acetylenedicarboxylate, and 2-oxo-2- phenylacetaldehyde that affords novel alkyl 2-benzoyl-4-alkylamino- 5-oxo-2,5-dihydro-3-furan carboxylate derivatives is reported. The reaction sequence consists of an initial Michael addition of primary amines to dialkyl acetylenedicarboxylates, followed by an aldol-like reaction with 2-oxo-2-phenylacetaldehyde, and then \gamma -lactonization to afford the products. This cascade reaction sequence represents a rapid and unprecedented route to the described biologically interesting molecules.

Preparation of Fully Substituted 1,3,4-Oxadiazole Derivatives from N-Isocyaniminotriphenylphosphorane, (E)-Cinnamic Acids, Chloroacetone and Primary Amines

Young Researchers Club, Zanjan Branch, Islamic Azad University, Zanjan, IranReceived June 5, 2011, Accepted June 29, 2011The 1:1 imine intermediate generated by the addition of primary amine to chloroacetone is trapped by N-isocyaniminotriphenylphosphorane in the presence of ( E)-cinnamic acids and the corresponding iminophosphoraneintermediate was formed. Disubstituted 1,3,4-oxadiazole derivatives are formed via intramolecular aza-Wittigreaction of the iminophosphorane intermediate. The reactions were completed in neutral conditions at roomtemperature. The disubstituted 1,3,4-oxadiazole derivatives were produced in excellent yields.Key Words : N-Isocyaniminotriphenylphosphorane, Chloroacetone, (E)-Cinnamic acid, 1,3,4-Oxadiazole,aza-Wittig reactionIntroductionRecently, multicomponent condensation reactions (MCRs)have become one of the most powerful methods for thesynthesis of small molecule libraries, due to the fact thatproducts are formed in a single step by simultaneous reactionsof several reagents and the molecular diversity required forsuch combinatorial libraries can be achieved by simplyvarying each component.

Reactions of nucleophilic addition of primary amines to the nitrilium derivative of the closo-decaborate anion [2-B10H9(N≡CCH3)

Compounds (Bu4N)[2-B10H9{NH=C(NHR)CH3}]− are obtained by reactions of the tetrabutylammonium salt of the [2-B10H9(N≡CCH3)]− anion with aliphatic and aromatic primary amines RNH2 (R = n-C3H7, n-C4H9, cyclo-C5H9, C6H5, cyclo-C6H11, n-C6H13, C7H7, C8H8NH2, C6H4NO2, and C18H37) and identified by IR, ESI/MS, and NMR (1H, 11B, and 13C) spectroscopy. The structures of the amidine-type derivatives [2-B10H9{Z-NH=C(NH-cyclo-C5H9)CH3}]− and [2-B10H9{Z-NH=C(NH-C7H7)CH3}]− are determined by X-ray diffraction.

Ortho-Selective Nucleophilic Addition of Primary Amines to Silylbenzynes: Synthesis of 2-Silylanilines

Ursache und Wirkung: Bei der Titelreaktion greifen primäre Amine trotz eines großen Trimethylsilyl-Substituenten die C2-Position von 3-Silylbenz-inen unter Bildung von 2-Silylanilinen an (siehe Schema). Dieser Reaktionsverlauf resultiert wahrscheinlich aus dem induktiven elektronenschiebenden Effekt der Silylgruppe, der gegenüber ihrer sterischen Abstoßung angreifender Amine überwiegt. Detailed facts of importance to specialist readers are published as ”Supporting Information”. Such documents are peer-reviewed, but not copy-edited or typeset. They are made available as submitted by the authors. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.

Ortho‐Selective Nucleophilic Addition of Primary Amines to Silylbenzynes: Synthesis of 2‐Silylanilines

Cause and effect: The first ortho-selective nucleophilic addition reaction of amines to 3-substituted benzynes has been achieved. Despite a large trimethylsilyl substituent, primary amines attack the C2 position of 3-silylbenzynes to produce 2-silylanilines (see scheme). This outcome is likely to result from the inductive electron-donating effect of the silyl group, which overrides its steric repulsion with the approaching amines.

Zinc(II) Triflate‐Catalyzed Divergent Synthesis of Polyfunctionalized Pyrroles

AbstractThe zinc(II) triflate‐catalyzed synthesis of highly functionalized pyrroles is described. The sequence involves the preliminary preparation of α‐aminohydrazones by Michael addition of primary amines to 1,2‐diaza‐1,3‐dienes. The treatment of these intermediates with dialkyl acetylenedicarboxylates produces α‐(N‐enamino)‐hydrazones that are converted into the corresponding pyrroles. The substituents on the carbon in position four of 1,2‐diaza‐1,3‐dienes drive the regioselectivity of the ring closure process. Starting from 4‐aminocarbonyl‐1,2‐diaza‐1,3‐dienes only dialkyl 1‐substituted 5‐aminocarbonyl‐1H‐pyrrole‐2,3‐dicarboxylates are achieved by Lewis acid‐catalyzed ring closure. A screening of several Lewis/Brønsted acid catalysts is performed. Zinc(II) triflate is the most efficient catalyst. Under similar reaction conditions, employing 4‐alkoxycarbonyl‐1,2‐diaza‐1,3‐dienes, only 4‐hydroxy‐1H‐pyrrole‐2,3‐dicarboxylates are synthesized. These latter reactions can be accomplished regioselectively also in one pot. Using 4‐aminocarbonyl‐1,2‐diaza‐1,3‐dienes, diamines and dialkyl acetylenedicarboxylates the sequence provides the corresponding α,ω‐di(N‐pyrrolyl)alkanes.

ChemInform Abstract: Stereospecific Synthesis of 2,3-Disubstituted Aziridines from β-Alkylamino Phenylselenides.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 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.

ChemInform Abstract: Gold Nanoclusters as a Catalyst for Intramolecular Addition of Primary Amines to Unactivated Alkenes under Aerobic Conditions.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 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.

An Experimental and Theoretical Study on the Remarkable Influence of Protecting Groups on the Selectivity of Addition of Amines to Vinyl Sulfone-Modified Hex-2-enopyranosides

Although phenylmethylene-protected vinyl sulfone-modified carbohydrate 2alpha reacts with both primary and secondary amines in Michael fashion to afford aminated products, only primary amines react with the dibenzyl-protected 3alpha, 6-O-trityl-protected 4alpha, and unprotected 5alpha, highlighting for the first time the remarkable influence of protecting groups on the reaction patterns of vinyl sulfone-modified carbohydrates. The quantum chemical calculations suggest that the Michael addition of amines and proton transfer to vinyl sulfone-modified carbohydrates 2alpha and 5alpha are possible via relay process in a concerted mechanism. These calculations reveal that the addition of primary amines to vinyl sulfone-modified carbohydrate is preferential due to the low activation energy barriers, whereas the addition of secondary amines has relatively higher activation energy barriers. The theoretical conclusions are in line with the experimental observations.