Morpholinoethyl Isocyanide

AldolCondensations. Cation-exchanged montmorillonites accelerate the aldol condensation of silyl enol ethers with acetals and aldehydes. Similarly, the aldol reaction of silyl ketene acetals with electrophiles is catalyzed by solid-acid catalysts. Neither report discussed the use of iron montmorillonite for these reactions however, some reactivity is anticipated. 

Miscellaneous Reactions. The coupling of silyl ketene acetals (enolsilanes) with pyridine derivatives bearing an electron-withdrawing substituent, namely cyano, in the meta position is catalyzed by iron montmorillonite and other similar solid-acid catalysts (eq 16).  

The resulting N-silyldihydropyridines easily undergo desilyla-tion by treatment with Cerium(IV) Ammonium Nitrate to afford the desired dihydropyridine derivative. The reactivity was found to be dependent on the montmorillonite counterion and to follow the order Fe + Co Zn + Np Sn.  

The Chemistry of Clay-Organic Reactions-, Hilger London, 1974. 

Cornelis, A. In Preparative Chemistry Using Supported Reagents-, Laszlo, R, Ed. Academic New York, 1987 pp 99-111. 

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Morpholinoethyl isocyanide Methyl ethyl ketone 2-Methoxyethoxymethyl... 

Although some solution-phase Ugi reactions were known to proceed rapidly, reaction times from 24 h to several days have been usually required for the solid phase. However, MWI-assisted solid-phase Ugi condensations of 2-morpholinoethyl isocyanide 475, aldehydes, and carboxylic acids in a mixture of dichloromethane and methanol (2 1) on amino-functionalized TentaGel S Ram as support gave... 

A rather different approach to peptide bond formation and amide synthesis in general is to treat a mixture of a carboxylic acid and an amine with an isocyanide 2-Morpholinoethyl Isocyanide is especially suitable), which effectively acts as a dehydrating agent (eq 3). The procedure can result in extensive racemization of both reactants and products which may be supressed by the addition of HOSu presumably an HOSu ester is the penultimate intermediate. The addition of HOSu also decreases racemization in polypeptide synthesis when Bates reagent [(Me2N)sP+]20 (BF4 )2 is used as the coupling agent. ... 

Introduction. The principal synthetic application of 2-morpholinoethyl isocyanide is as a coupling reagent of amino acids to yield peptides. It also reacts with aldehydes or ketones to yield amides, with acids to yield imidazolinium salts, and has been used as a ligand in spectroscopic studies to examine shielding effects ... 

Coupling of Amino Acids. The coupling reaction is performed in CH2CI2 with N-Hydroxysuccinimide or f-Hydroxybenzotriazole and 2-morpholinoethyl isocyanide (1) to yield products in 61-95% yield (eq 1). 

Peptides. This isocyanide is preferable to simple aliphatic isocyanides (9, 82) for coupling of amino acid derivatives to peptides. Addition of hydroxysuccinimide (9,246) or 1 -hydroxybenzotriazole (6,288) suppresses racemization. It is important to allow the acid component and the additive to react with the isocyanide for a suitable period before addition of the amine component and triethylamine or DMAP. Coupling to di- and tripeptides in yields of 55-72% have been reported. The byproduct, (N-morpholinoethyl)formamide, is removed by an acid wash. 

Cyclohexylcyclohexanone, 180-181 Cyclohexyl fluoride, 627 N-Cyclohexylformamide, 382, 857, 878 Cyclohexylformyl peroxide, 57 Cyclohexylidenecyclohexylamine, 788 C clohexyl iodide, 94, 553, 873 C clohexyl isocyanide, 382, 857, 878 Cyclohexyl isothiocyanate, 181 Cyclohexylmagnesium bromide, 1232 Cyclohexyl methyl ether, 72-73 l-Cyclohexyl-3-(2-morpholinoethyl)-... 

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