微波辐射下N-芳基甲酰胺的合成

以甲酸作为甲酰化试剂，通过微波辐射合成的11种N-芳基甲酰胺。产率比传统 方法有所提高，反应时间缩短了20-120倍。     

An efficient reduction of N-substituted carbonylimidazolides into formamides by NaBH4

A novel, simple and versatile protocol was investigated for highly efficient synthesis of formamides through reducing N-substituted carbonylimidazolides by NaBH₄ under mild reaction conditions. By this method, not only carboxylic acids or isocyanates, but also amines can readily access formamides with high yields.     

Microwave Assisted Amine Formylation by a Heterogeneous HCO2H/SiO2 System

A simple, fast and efficient procedure has been developed for the synthesis of formamides by treating a silica gel/formic acid mixture with amines under microwave irradiation.     

Microwave-assisted synthesis of isonitriles: a general simple methodology

[reaction: see text] A facile conversion of formamides to isonitriles under very mild conditions and microwave irradiation is described. This simple and efficient method has been applied for the synthesis of both aliphatic and aromatic isonitriles in high yields.     

A novel reductive coupling reaction between diphenylphosphine sulfide and formamides

The coupling reaction of diphenylphosphine sulfide with N,N-disubstituted formamides in the presence of an excess amount of sodium hydride proceeded smoothly to give the corresponding aminomethyldiphenylphosphine sulfides in good yields. This method is expected to provide a useful synthesis of P,N-containing ligands.     

Transition metal-free direct amination of benzoxazoles using formamides as nitrogen sources

A transition metal-free method for the direct amination of benzoxazoles using formamides as nitrogen sources is reported, which was mediated by an inexpensive and environmentally friendly tetrabutylammonium iodide/tert-butyl hydroperoxide system and gave the 2-aminobenzoxazole derivatives with moderate to good yields.     

A new synthesis of β-amino acids by use of ketene diethyl acetal as enolate equivalent

Reaction of phenylsulfonyl formamides, readily available in a single step from an aromatic aldehyde and sodium phenylsulfinate, with ketene diethyl acetal under basic conditions gives N-formyl β-amino acid esters in good yield, which can be kinetically resolved with a lipase.     

Potassium tert-butoxide-mediated metal-free synthesis of sulfonamides from sodium sulfinates and N,N-disubstituted formamides

By using formamides as amine sources, a novel and efficient KO-t-Bu mediated amination of sodium sulfinates has been developed. The reaction utilizes readily available starting materials under metal-free conditions, thus providing an alternative and attractive route to sulfonamides.     

Synthesis of O-unprotected glycosyl selenoureas. A new access to bicyclic sugar isoureas

β-d-Gluco and mannopyranosyl selenoureas have been prepared by coupling of the corresponding glycosylamines with phenyl isoselenocyanate in aqueous pyridine. Alkyl and aryl isoselenocyanates, and 1,4-phenylene diisoselenocyanate have been obtained from the corresponding formamides with an excess of triphosgene, black selenium and triethylamine. Treatment of the O-unprotected β-d-glucopyranosyl selenourea with aqueous oxygen peroxide afforded a 1,2-trans-fused bicyclic isourea.     

Unexpected formation of N,N-disubstituted formamidines from aromatic amines, formamides and trifluoroacetic anhydride

An intriguing selectivity towards the formation of the formamidine was observed upon the reaction of an amine with sodium hydride and trifluoroacetic anhydride in dimethyl formamide. Various aromatic amines were reacted with a series of N,N-disubstituted formamides as a solvent under the influence of trifluoroacetic anhydride to thoroughly probe this behaviour. A trend in selectivity is discussed and a proposed mechanism for the reaction is also presented.     

Efficient synthesis of β-enaminoesters via highly stereoselective Reformatsky reaction with disubstituted formamides as novel electrophiles

An efficient synthesis of various β-enaminoesters has been achieved via Reformatsky reaction with disubstituted formamides as novel electrophiles. The exclusive β-enaminoester E-isomers were obtained in 60-72% yield.     

Tetrabutylammonium chloride-triggered 6-endo cyclization of o-alkynylisocyanobenzenes: an efficient synthesis of 2-chloro-3-substituted quinolines

A highly efficient one-pot synthesis of 2-chloro-3-substituted quinolines has been developed by tetrabutylammonium chloride-triggered 6-endo cyclization of o-alkynylisocyanobenzenes, which are generated in situ by dehydration of the corresponding N-(2-ethynylphenyl)formamides.     

The action of substituted formamides on arylformylacetonitriles

The reaction between phenyl- or p-methoxy phenylformylacetonitrile and monosubstituted formamides results in enaminonitriles. In some instances a simultaneous deformylation is observed. Formic acid is produced during the reaction and its origin was investigated.     

Stereoselective intramolecular 1,3-dipolar nitrile oxide cycloaddition reaction of N-formyl-β-nitroamides

The stereoselective intramolecular nitrile oxide cycloaddition (INOC) reaction was achieved from N-formyl-β-nitroamides, which were prepared through the Michael addition of allylic formamides to nitroalkenes, and cis-pyrroroisoxazoles and trans-piperidinoisoxazoles were obtained in a stereoselective manner.     

Chiral 1,3-diamines from a lithiated isocyanide and chiral aziridines

Reaction of lithiated 4-methoxybenzylisocyanide with homochiral amino acid derived N-tosyl- and N-diphenylphosphinoylaziridines proceeds diastereoselectively to provide N-protected 3-isocyanoamines. Separation of the diastereomers of these adducts or the corresponding formamides, and subsequent transformations, lead to 1,3-diamines and their monoprotected and differentially bisprotected derivatives.     

A convenient synthesis of 2-substituted indoles by the reaction of 2-(chloromethyl)phenyl isocyanides with organolithiums

The reaction of 2-(chloromethyl)phenyl isocyanides, readily available by dehydration of the respective N-[2-(chloromethyl)phenyl]formamides, with organolithiums produced 2-substituted indoles in satisfactory yields through addition of organolithiums to the isocyano carbon followed by intramolecular substitution reaction of the resulting imidoyl anion intermediates.     

Silver Catalyzed Decarbonylative [3 + 2] Cycloaddition of Cyclobutenediones and Formamides

As an important moiety in natural products, N,O-acetal has attracted wide attention in the past few years. An efficient method to construct N,O-acetal has been developed. Using silver catalyst, cyclobutenediones were smoothly converted to the corresponding γ-aminobutenolides in the presence of formamides, in which cyclobutenediones likely proceed with a key decarbonylative [3 + 2] cycloaddition process. In this way, a series of products with varied substituents were isolated in moderate yield and fully characterized.     

A convenient synthesis of (E)-α-alkylidene-γ-lactams and (E)-3-alkylideneoxindoles by rhodium-catalyzed intramolecular hydroamidation

Rhodium-catalyzed carbonylative cyclization without carbon monoxide was investigated. Cyclization of various formamides having alkynyl groups proceeded smoothly in the presence of Rh₄(CO)₁₂ to provide α-alkylidene-γ-lactams or 3-alkylideneoxindoles in moderate to good yields with high (E)-selectivity.     

Ultrasound-assisted tandem synthesis of tri- and tetra-substituted pyrrole-2-carbonitriles from alkenes,TMSCN and N,N-disubstituted formamides

An energy-saving and eco-friendly method for the efficient construction of various tri- and tetra-substituted pyrrolecarbonitriles through ultrasound-assisted multicomponent tandem reaction of readily available alkenes, TMSCN and N,N-disubstituted formamides within 40 min under metal-, solvent-free and mild conditions was developed. The dual role of iodine (catalyst and oxidant) notably simplified the reaction conditions and reduced the chemical waste generated     

Palladium-catalyzed carbon-monoxide-free aminocarbonylation of aryl halides using N-substituted formamides as an amide source

A carbon-monoxide-free aminocarbonylation of various N-substituted formamides with aryl iodides and aryl bromides using palladium acetate and Xantphos is described. The developed methodology is applicable for a wide range of formamides and aryl halides containing different functional groups furnishing good to excellent yield of the corresponding products. N-substituted formamides are used as an amide source wherein a Vilsmeier-type intermediate plays a major role, thus eliminating the need of toxic carbon monoxide gas.