Synthesis Of Formamides Research Articles

The Two Faces of Sulfinates: Illustrating Umpolung Reactivity

A simple, microscale experiment was developed with the aim of demonstrating the concept of umpolung in synthetic organic chemistry. Starting from a common alkyl sulfinate, students perform a polarity inversion by performing a Grignard-based sulfoxide synthesis and a Mannich-type formamide synthesis. The products are purified without chromatography and are easily characterized. Procedural optimization established an experiment time of less than 3 h. Spectroscopic characterization includes the interpretation of 1H NMR, 13C NMR, and FTIR spectra. This experiment, therefore, is suitable for a mid- to upper-level undergraduate organic lab curricula for illustrating advanced synthetic methods.

Formamide Synthesis through Borinic Acid Catalysed Transamidation under Mild Conditions.

A highly efficient and mild transamidation of amides with amines co-catalysed by borinic acid and acetic acid has been reported. A wide range of functionalised formamides was synthesized in excellent yields, including important chiral α-amino acid derivatives, with minor racemisation being observed. Experiments suggested that the reaction rely on a cooperative catalysis involving an enhanced boron-derived Lewis acidity rather than an improved Brønsted acidity of acetic acid.

Preparation, characterization and application of nanosized CuO/HZSM-5 as an efficient and heterogeneous catalyst for the N-formylation of amines at room temperature

An efficient and new method for the synthesis of formamides using HZSM-5 zeolite supported copper oxide nanoparticles as an efficient and heterogeneous catalyst is reported. The catalyst was characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), atomic absorption spectroscopy (AAS), Brunauer-Emmett-Teller (BET), energy dispersive X-ray spectroscopy (EDS), temperature programmed desorption of ammonia (TPD-NH3) and Fourier transformed infrared spectroscopy (FT-IR). This method has the advantages of eliminating homogeneous catalysts and provides simple methodology with easy work up. Excellent yields of the corresponding formamides were obtained through this cost-effective protocol under solvent-free conditions with shorter reaction time. The catalyst was easily isolated from the reaction mixture by filtration and reused several times without significant loss in its catalytic

Synthesis of formamide and isocyanic acid after ion irradiation of frozen gas mixtures

Context. Formamide (NH2 HCO) and isocyanic acid (HNCO) have been observed as gaseous species in several astronomical environments such as cometary comae and pre- and proto-stellar objects. A debate is open on the formation route of those molecules, in particular if they are formed by chemical reactions in the gas phase and/or on grains. In this latter case it is relevant to understand if the formation occurs through surface reactions or is induced by energetic processing.Aims. We present arguments that support the formation of formamide in the solid phase by cosmic-ion-induced energetic processing of ices present as mantles of interstellar grains and on comets. Formamides, along with other molecules, are expelled in the gas phase when the physical parameters are appropriate to induce the desorption of ices. Methods. We have performed several laboratory experiments in which ice mixtures (H2 O:CH4 :N2 , H2 O:CH4 :NH3 , and CH3 OH:N2 ) were bombarded with energetic (30–200 keV) ions (H+ or He+ ). FTIR spectroscopy was performed before, during, and after ion bombardment. In particular, the formation of HNCO and NH2 HCO was measured quantiatively.Results. Energetic processing of ice can quantitatively reproduce the amount of NH2 HCO observed in cometary comae and in many circumstellar regions. HNCO is also formed, but additional formation mechanisms are requested to quantitatively account for the astronomical observations. Conclusions. We suggest that energetic processing of ices in the pre- and proto-stellar regions and in comets is the main mechanism to produce formamide, which, once it is released in the gas phase because of desorption of ices, is observed in the gas phase in these astrophysical environments.

Amine modified mesoporous Al2O3@MCM-41: an efficient, synergetic and recyclable catalyst for the formylation of amines using carbon dioxide and DMAB under mild reaction conditions

A novel amine modified meso Al2O3@MCM-41 catalyst was investigated for the synthesis of formamides from 1°/2° aliphatic as well as aromatic amines with CO2, using DMAB.

ChemInform Abstract: Applications of Metal Nanopore Catalysts in Organic Synthesis

AbstractReview: [129 refs.

K3PO4-catalyzed carbonylation of amines to formamides

Synthesis of formamides from the catalytic carbonylation of amines with CO is of great interest due to their wide applications of formamides as synthetic intermediates and aprotic polar solvents. Up to now, the most commonly used catalysts are either expensive noble metal compounds or difficult-to-handle alkali metal alkoxides. We have found that a solid base, K3PO4 is a highly active and selective catalyst for the carbonylation of primary and cyclic secondary amines, producing corresponding formaldehydes in yields up to 99% at relatively mild conditions. Spectroscopic and quantum mechanical calculation results indicate that such high activity of K3PO4 is closely related to the strong hydrogen bonding ability of PO43− with the amino group of an amine, thereby enhancing the nucleophilicity of the amino group enough to interact with a neutral molecule, CO and mediating proton transfer from the amino group to the carbonyl group. Characterization of spent catalyst by FT-IR and XRD implies that small portion of K3PO4 is converted into less active K2HPO4 during the carbonylation reaction.

Preferential cleavage of C[sbnd]C bonds over C[sbnd]N bonds at interfacial CuO[sbnd]Cu2O sites

Creation of substrate-accessible interfacial defect sites will bring about new catalytic discoveries because substrate binding and activation on these sites are pivotal for controlling reaction intermediate and product selectivity. The partial oxidation of pristine Cu2O can lead to an excellent selective oxidation catalyst (CuO/Cu2O). The CuO/Cu2O, containing embedded CuO nanodomains on the surface and possessing abundant coordinatively unsaturated copper sites at the CuOCu2O interface, shows very high activity toward CC bond cleavage and excellent selectivity toward formamides in trialkylamines oxidation. This result is exceptional because the previous works mainly offer dealkylated amines via CN bond cleavage. The unusual catalysis by CuO/Cu2O is attributed to the co-activation of oxygen and amines in close proximity at the CuOCu2O interface. The present study contributes a new concept of delicate controlling substrate-accessible interfacial active sites on pristine oxide surfaces, and also offers a novel formamide synthesis method by trialkylamine oxidation.

Applications of Metal Nanopore Catalysts in Organic Synthesis

Reducing the size of bulk metals to nanometer scale can result in the display of extraordinary physical and chemical properties. Typically, metal nanoparticles (MNPs) are prepared from metal atoms or metal salts and show remarkable catalytic properties. Metal nanopores (MNPores) are prepared through a totally reverse approach (from bulk metal to nanosized metal): alloy M¹M² is fabricated from metal M¹ and metal M², and then dealloying of M² results in a nanoporous framework of metal M¹. This account summarizes MNPore-catalyzed reactions developed in our group, and their comparison with other representative catalytic reactions. 1 Introduction 1.1 Fabrication and Structural Characteristics of Nanoporous Gold 2 Oxidation Reactions 2.1 Oxidation of Alcohols 2.2 Synthesis of Formamides Through Oxidative Coupling of Methanol with Amines 2.3 Oxidation of Silanes 3 Reduction Reactions 3.1 Semihydrogenation of Alkynes 3.2 Reduction of Quinoline 3.3 Reduction of Imines and Reductive Amination of Carbonyls 3.4 Reduction of α,β-Unsaturated Aldehydes 3.5 1,4-Hydrosilylation of Cyclic Enones 4 Formation of C–Si, C–B, and C–C Bonds Using Alkynes 4.1 Hydrosilylation of Alkynes 4.2 Diboration of Alkynes 4.3 Benzannulation Reaction 5 CuNPore-Catalyzed Click Reaction 6 Suzuki, Negishi and Heck Coupling Reactions 7 Concluding Remarks

Reductive Transformation of CO2 with Hydrosilanes Catalyzed by Simple Fluoride and Carbonate Salts

Abstract Hydrosilylation of CO2 catalyzed by simple fluoride and carbonate salts, such as CsF and K2CO3, is described. Total yields up to 87% for the formylated product were achieved. Mechanistic investigations indicate the reaction proceeds via the formation of an active formate species. This catalytic system was also found to be applicable to formamide synthesis from amines, CO2, and hydrosilane.

An Eco-friendly N-formylation of Amines Using Nano Cerium Oxide as a Recyclable Catalyst Under Solvent-free and Ultrasound Irradiation Conditions at Room Temperature

A new method for the synthesis of formamides has been developed by the N-formylation of amines with formic acid in the presence of nano cerium oxide as an efficient and recyclable catalyst under ultrasound irradiation. The reaction system is remarkably simple and environmentally benign.

ChemInform Abstract: Selective Aerobic Oxidation of Methanol in the Coexistence of Amines by Nanoporous Gold Catalysts: Highly Efficient Synthesis of Formamides.

AbstractA highly efficient access to formamides by gold‐catalyzed aerobe oxidative reaction of methanol and various primary and secondary amines with good to excellent yields is presented.

ChemInform Abstract: Nano CoFe2O4 as a Magnetically Separable Catalyst for the Solvent‐Free Synthesis of Formamides under Ultrasound Irradiation at Room Temperature.

AbstractA protocol for the ultrasound assisted formylation of secondary and primary amines is described.

Synthesis and characterization of copper nanoparticles supported on reduced graphene oxide as a highly active and recyclable catalyst for the synthesis of formamides and primary amines

We report here the synthesis of reduced graphene oxide supported copper nanoparticles (rGO/Cu NPs) from copper (II) sulfate pentahydrate and graphite precursors using a simple protocol. The catalyst was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), Brunauer–Emmett–Teller (BET) and energy dispersive X-ray spectroscopy (EDS). The rGO/Cu NPs is proved to be a useful heterogeneous catalyst in Cu-catalyzed formamidation and amination of arylboronic acids. The catalyst can be recovered by simple filtration from the reaction mixture and reused several times without significant loss of catalytic activity.

ChemInform Abstract: Unexpected Route for the Synthesis of N,N‐Dialkyl Formamidines Using Phenyl Chloroformate and N,N‐Dialkyl Formamides.

AbstractIt is discovered that phenyl chloroformate can be used as an efficient dehydrating agent for the synthesis of formamides from a variety of primary amines and N,N‐dialkyl formamides by using short reaction times and mild conditions.

TiO2 NPs as Catalyst for N-Formylation and N-Acetylation of Amines under Solvent–Free Conditions

Anatase phase TiO2- nanoparticles (TiO2 NPs) used as a heterogeneous and highly efficient catalyst for the synthesis of formamides and acetamides by reacting the structurally diverse amines with formic acid and acetic anhydride or acetic acid, respectively, under solvent-free conditions at room temperature. Chemoselectivity, mild and heterogeneous conditions, clean work-up and high reaction yields make this method practical for organic transformations. Keywords: TiO2- nanoparticles, N-formylation, N-acetylation, formamides, acetamides, solvent-free.

Selective Aerobic Oxidation of Methanol in the Coexistence of Amines by Nanoporous Gold Catalysts: Highly Efficient Synthesis of Formamides

Holey gold: Highly selective aerobic oxidation of methanol over alkylamines was achieved with a reusable nanoporous gold (AuNPore) catalyst that was fabricated from a Au-Ag alloy. This excellent chemoselectivity enabled direct N-formylation of alkylamines from a mixture of methanol and amines. The remarkable catalytic activity was attributed to the synergistic effect between gold and the residual silver remaining in the AuNPore.

Nano CoFe2O4 as a Magnetically Separable Catalyst for the Solvent-free Synthesis of Formamides Under Ultrasound Irradiation at Room Temperature

Formamides were efficiently synthesized from N-formylation of amines using CoFe2O4 nanoparticles as a magnetically recoverable and reusable catalyst under ultrasound irradiation. The main advantages allocated to this method are chemoselectivity, reduced reaction times, high yields, magnetically recyclable catalyst, non-solvent green conditions and simple work-up procedure. Keywords: N-formylation, amine, formic acid, sonochemistry, nano CoFe2O4.

Protic [TBD][TFA] ionic liquid as a reusable and highly efficient catalyst for N-formylation of amines using formic acid under solvent-free condition

Trifluoroacetate guanidinium salt [TBD][TFA] ionic liquid was used as a recyclable and reusable catalyst for the synthesis of formamides. Primary and secondary amines were reacted with formic acid to afford N-formyl derivatives in high yield under solvent-free condition at room temperature.

Green synthesis of formamides using the Natrolite zeolite as a natural, efficient and recyclable catalyst

Chemoselective N-formylation of different amines was carried out with formic acid in the presence of the Natrolite zeolite as an efficient, stable and natural heterogeneous catalyst to give the corresponding formamides at room temperature under solvent-free conditions. This method has the advantages of high yields, mild conditions, simple methodology, easy work up and short reaction times. The catalyst was characterized by different techniques such as powder XRD, XRF, TGA–DTA, SEM and FT-IR spectroscopy. The Natrolite zeolite was recovered and reused several times without the significant loss of its catalytic performance.