Benzaldehyde sulphur-containing derivatives

Cl Vat Blue 43 and the equivalent dye derived from N-ethylcarbazole (Cl Vat Blue 42) are sometimes referred to as sulphurised vat dyes. This term is also applied to some anthraquinonoid thiazole derivatives, such as Cl Vat Yellow 2 (6.151). This compound can be made by the reaction of 2,6-diamino-l,5-dichloroanthraquinone with benzaldehyde and sulphur. Another anthraquinonoid vat dye containing a thiazole ring system (6.107) has already been mentioned. 

Baker and his co-workers [60,61] investigated the influence of the sulphuric acid concentration in nitrating mixtures on the meta- nitro derivatives of the following compounds benzaldehyde, benzophenone and ethyl benzoate. The content of a meta- nitro derivative increases with the increase in acidity of the solution. For example, in nitration with a nitrating mixture containing 80% sulphuric acid the yield of m- nitrobenzaldehyde is 83.9%. When nitrated with a mixture containing... 

Pentafluorophenylhydrazine, in a condensation reaction with 27 carbonyl compounds, gave quantitative results for most of them [59]. The minimum detectable amount was 0.01 ng, the derivatives being separated in a column coated with SE-30 or PEG 20M. Hoshika [60] used derivatives containing sulphur for the GC analysis of benzaldehyde, which were prepared by condensation with 2- and 3-methylthioaniline (Scheme 5.7). 

Ether linkages in open-chain bolaamphiphiles were obtained in a 20% isolated yield from a,o)-dibromoeicosane with an alcohol in THF containing sodium hydride (Scheme 2.8). The synthesis of macrocyclic tetraethers was unsuccessful. Attempts to reduce macrocyclic lactones with four ester groups via a variety of methods failed. The production of macrocyclic thioacetals from benzaldehyde derivatives and a,to-dithiols was unproblematic and produced quantitative yields (Scheme 2.8). The cyclization of 2,2-thiodiethanol with a,(o-diols in the melt and in the presence of /7-toluenesulfonic acid is an intermediate case. Apolar macrocycles were obtained in 50% yield. 5-(2-hydroxyethyl)thiiranium ions are presumably formed as reactive intermediates during the ether formation steps. The sulphur atom was oxidized to the... 

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