Amino group reactions

The addition of nucleophiles to double and triple bond systems is often a convenient way of effecting an intramolecular ring closure. Addition to cyano groups has received considerable attention, as in addition to ring formation it provides a convenient method for the introduction of an amino group. Reaction of methyl Af-cyanodithiocarbimidate with Af-methylaminoacetonitrile resulted in displacement of methanethiol and formation of (314). Sodium ethoxide treatment in DMF converted (314) into a 4-amino-5-cyanoimidazole... 

Amino group reactions (e.g. acylation) proceed best under basic conditions, whereas carboxyl group reactions (e.g. esterification) are effected under acidic conditions with the amino function protected by protonation. 

Also acetic acid may arise from a reaction of this type. Most important compounds of this pathway are pyruvic aldehyde, diacetyl, hydro-oxyacetone and hydroxydiacetyl which can easily react with amino acids. The Strecker degradation is a reaction where the amino acid is de-carboxylated and loses its amino group. Reaction products are the Strecker aldehyde and - as an intermediate - an aminoketone which forms a pyrazine by dimerization. This pathway is considered to be most important for the origin of pyrazines in thermal aromas. However, only limited knowledge is available about the fate of the Strecker aldehydes. As we will demonstrate they are very reactive. 

The reactions of Cp2TiCl2 with 2,6-diacetylpyridine-bis(S-alkylisothiosemicarbazones) give bis-Cp complexes with isothiosemicarbazone ligands coordinated to the titanium atom which contain terminal free amino groups. Reactions of these derivatives with /3-diketones have been carried out to afford cyclic complexes.1584... 

Preparation of biotin derivatives active with groups other than amino groups (reactions... 

The adsorption of CO2 on PEI-MPS is an exothermic process mainly based on the reaction of CO2 with the amino groups (reaction 1). The amount of CO2 adsorbed is proportional to the generated heat. In this study, the heat released during CO2 adsorption was monitored by a Micro Reaction Calorimeter (URC) operating at the isothermal mode (Figure 1). 

The reaction of hindered secondary amines with 2-chloroethyl carbonates and acetates to form tetrasubstituted ethylenediamines is another process which appears to take place by bimolecular alkyl cleavage with neighboring-group participation of the amino group (reaction 17). Other examples of neighboring amino-group participa-... 

BREMNER J.M. 1957. Studies on soil humic acids II. Observations on the estimation of free amino groups. Reactions of humic acid and lignin preparations with nitrous acid. Journal of Agricultural Science, 48, 352-360. 

The dipeptide that is protected at both the carboxyl and amino terminus is deprotected by hydrolysis of the Boc group at the N-terminal amino acid. The dipeptide can only react at the free amino group. Reaction with another Boc-amino acid and DCCI yields a tripeptide. At the end of the synthesis, the final peptide is released by hydrolysis with base. 

Benzyl bromide will readily alkylate amino groups. Reactions are normally carried out in the presence of additional base and dibenzylation of primary amines is usually predominant. Selective quatemization of a less hindered tertiary amine in the presence of a more hindered tertiary amine has been described." Amide and lactam nitrogens can be benzylated under basic conditions, as can those of sulfonamides" and nitrogen heterocycles. ... 

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