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Anil compounds are Schiff bases derived from aniline moiety containing phenyl or substituted phenyl group, which sometimes called Azo dyes. These Schiff bases can be directly prepared from aromatic amine with aromatic carbonyl groups, which are stable and can be manipulated under different and suitable conditions. The phenomena of coordination of Schiff bases with metal ions give the Schiff bases the good advantages to be introduced in the dyes synthesis. The classification of dyes is based on the chemical structure or on the basis of the chromophoric system. The metal complex dyes are combinations of dyestuff and metal ions, in which the coordination complex can be applied or used to be improvement factors in dye techniques. The investigation and the characterization of the resulted dyes were performed by using different physical techniques. The produced dyes were applied to different fibres, such as sheep wool and goat hair with two Schiff bases synthesised from salicylaldehyde either with 2-aminophenol or 2-aminobenzyl alcohol. Also the investigation includes the effect of mordant type on the dyeing process.

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Abstract The amino acids alanine, valine, leucine, isoleucine, norvaline, α-amino butyric acid, and β -methyl aspartic acid are utilized as substrates for organocobalamin syntheses under “oxidizing/reducing” conditions. In the presence of V+3 as the reducing agent, free radicals are generated by the reaction of oxygen radicals with the amino acids through hydrogen atom abstraction. These amino acid radicals then combine with the cobalt atom of vitamin B12r to yield the respective organocobalamins. The cobalamin obtained from the reaction of β-methyl aspartic acid is a possible intermediate in the coenzyme B12 dependent skeletal rearrangement of β-methyl aspartic acid to glutamic acid. HPLC analysis of the cobal-amins prepared from D, L-alanine indicates that the corrin ligand is relatively ineffective at promoting asymmetric syntheses under these conditions.

AbstractSyntheses of methylcobalamin from methane, and of n-alkylcobalamins from n-alkanes (C2→C10) and vitamin B12r are described. The compounds are formed under "oxidizing-reducing" conditions: Oxygen radicals (O2-, HOO·, and HO·) are generated from the reaction of O2 with reducing metal ions, notably V+3 (aq) and abstract hydrogen from the alkane substrates. The resulting alkyl radicals are captured by vitamin Bj2r with high efficiency to yield alkylcobalamins. The reactions take place at room temperature in mildly alkaline or acidic solutions. In addition to n-alkylcobalamins, the preparation of neopentylcobalamin from neopentane, of isobutylcobalamin from isobutane, and of several cycloalkylcobalamins from cycloalkanes, is also reported. Methyl radicals generated in D2O from CH4 under "oxidizing-reducing" conditions are reduced to yield CH3D.