Amine isonitrile

The four component condensation (Ugi reaction) " converts a mixture of substituted amine, isonitrile, aldehyde (or ketone) and carboxylic acid (Scheme 6) to a-acylaminocarboxylic acid amides (pathway a), to diacylamines (pathway b) and to a-aminocarboxylic acid amides (pathway... 

In an elegant and different approach, an array of C-linked, glycopeptide-like mimics of SLex were synthesized in parallel by an Ugi four-component reaction. Reaction of different anomeric two- or three-carbon extended C-glycosyl aldehydes or acids with resin-bound amine, isonitriles and with other acids or aldehydes, respectively, yielded an array of C-linked analogues. The method is easy to perform in good yield on solid phase. How-... 

The rare earth tricyclopentadienyls are insoluble in aliphatic hydrocarbons, and only sparingly soluble in aromatic hydrocarbons. They dissolve in polar solvents like tetrahydrofuran with complexation. Similarly, numerous bases like ethers, amines, isonitriles, phosphines and other compounds react with CP3R, yielding stable 1 1... 

Keywords orf/to-Phthalaldehyde/ 3,4-dimethoxy ori/to-phthalaldehyde, amines, isonitriles, NaHS03, DMSO-H2O (1 1), room temperature, one-pot three-component reaction, 1-car-boxamido-3-oxoisoindoles... 

In one of the initial such examples, Domling and coworkers have reported both Ugi and Passerini-type MCR in concert with RCM. The general approach is outlined in Scheme 11.25, with the linear precursor (186) obtained from the MCR then subjected to standard RCM to give the macrocyclic products 187 or 188. In this manner, the representative 22-membered macrocycle (189) is produced from the Ugi four-component coupling reaction (4CR) of an acid, amine, isonitrile and paraformaldehyde. In a similar way, the exemplary 17-membered macrocycle (190) was prepared from the Passerini SCR of an acid, aldehyde and isonitrile. Methods for the synthesis of the starting materials also needed to be developed to ensure sufficient... 

CH3)3Si)2N]2U(CH2Si((CH3)2)N(Si(CH3)3)) Generally, uranium metaUacycles are quite reactive inserting a host of organics, ie, CO, secondary amines, nitriles, isonitriles, aldehydes, ketones, and alcohols. 

ISONITRILES. This designation includes isocyanides (see Vol 3, C582-L to C583-L and Vol 7, I135-R for Cyanicic Acid and-Derivatives) and Carbylamines, R.NiC. The first isonitriles were prepd in 1886 by Gautier, by the action of Ag cyanide on alkyl iodides. Later, Hofmann prepd them by the action of chlf ale KOH on primary amines ... 

The isonitriles are reactive, volatile liqs with an extremely repulsive odor. Their formation is often used as a method for the detection of primary amines... 

Efficient stirring is required. A solution of 225 g. (5.6 moles) of sodium hydroxide in 225 ml. of water can be added to the stirred mixture of the organic substrates in dichloromethane if a more efficient mechanical stirrer is used. In the original procedure, the submitters noted an induction period of about 20 minutes which was stated to vary somewhat with the stirring rate, stirring-bar size, and relative amount of phase-transfer catalyst. Three moles of base are required for the reaction one to generate the carbene and two to react with the additional two moles of hydrochloric acid lost by the amine-carbene adduct in the isonitrile formation step. If less base is used, the excess hydrochloric acid reacts with the isonitrile by a-addition, and the yield is substantially reduced. 

Yields higher than about 70% for any of these isonitrile preparations generally indicate incomplete fractionation. The purity of the product may be conveniently checked by proton magnetic resonance spectroscopy. The characteristic 1 1 1 triplet for tert-butyl isocyanide appears at <5 1.45 (chloroform-d). A small upheld peak usually indicates the presence of unreacted amine. Other common contaminants are dichloromethane and chloroform The purity may be determined more accurately by gas chromatographic analysis on a 230 cm. by 0.6 cm. column packed with 10%SE30 on Chromosorb G, 60-80 mesh, at 80°. 

Isonitrile werden durch Lithiumalanat in Ather mit guten Ausbeuten zu Methyl-al-kyl(ary 1) - aminen reduziert z. B. Phenyl-isonitrilzu N-Methyl-anilin (79°/o d. Th.)1. Mit Bis-[2-methyl-propyl]-aluminiumhydrid wird das Isonitril bis zur Imino-Stufe reduziert, und man erhalt nach Hydrolyse prim. Amine und Formaldehyd2 ... 

Ligand A anionic (e.g., halides, pseudohalides, alkyl, aryl, thiolate, alkoxide) ligand N neutral (e.g., amines, imines, phosphines, carbenes, nitriles, isonitriles, NO, CO) ligand C cationic (e.g., NO+)... 

Tin-mediated-radical cyclization of isonitriles provides a useful strategy for the preparation of indoles (Fukuyama reaction).90 This radical cyclization is used for synthesis of 6-hydroxy-indole-3-acetic acid, which is the aromatic subunit of Nephilatoxin. The requisite isonitriles are prepared from nitroarenes via amines (Eq. 10.66).91... 

A four-component Ugi reaction between the thienopyrrole-diketo-acid 280, an isonitrile and an amine gives the fused tricycle 281 with two nitrogens in the six-membered ring <2006SC903> (Equation 44). 

Another method for preparing pyrrole rings is by Ugi-type three-component condensation (Scheme 6.184). In the protocol published by Tye and Whittaker [345], levulinic acid was reacted with two different isonitriles and four amine building blocks (1.5 equivalents) to provide a set of eight pyrrole derivatives. While the previously published protocol at room temperature required a reaction time of up to 48 h and provided only moderate product yields, the microwave method (100 °C, 30 min) optimized by a Design of Experiments (DoE) approach (see Section 5.3.4), led to high yields of the desired lactams for most of the examples studied. 

The best results in the imidazole synthesis were obtained by microwave-assisted reaction of an eightfold excess of the polymer-supported isonitrile suspended in 1,2-dimethoxyethane (DME) with the appropriate amines. Cleavage with 50% trifluoroacetic acid in dichloromethane afforded the desired heterocyclic scaffolds in moderate yields. 

Finally, Odom and co-workers reported a titanium-catalyzed three-component coupling between primary amines, alkynes, and isonitriles for the preparation of a, 3-unsaturatcd /3-iminoamines in good yields (Scheme 35).121 Beside the three-component coupling product, an. V,.V-disubstituted formamidine and an imine were also identified as minor... 

Based on the established mechanism for titanium-catalyzed hydroamination, the authors propose a reversible reaction between a titanium imide complex and the alkyne to form metalloazacyclobutene 86, which in turn undergoes 1,1-insertion of the isonitrile into the Ti-C bond. The generated five-membered ring iminoacyl-amido complex 87 with the new C-C bond is protonated by the primary amine to afford the desired three-component coupling product, with regeneration of the catalytic imidotitanium species. Very recently, titanium-catalyzed carbon-carbon bond-forming reactions have been reviewed.122... 

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