Morg

Awodiya Toluwani, 'scarred' painting.

took just one pic today cause I didn't have a lot of time. looks a lot like yesterday's orchard pic but with that nice low evening sun that lights up all the dandelion seeds.

If there's any dyestuff I'd love to say I made for myself it's the first ever commercially practical synthetic dye, Perkin's mauve or "mauveïne", which the pioneering organic chemist William Henry Perkin made by accident while pursuing an extremely naïve synthesis of quinine by oxidation of aniline and toluidine mixtures. (Aniline is aminobenzene, C₆H₅NH₂. Toluidine is aniline with an extra methyl group on the aromatic ring, CH₃C₆H₄NH₂, and there's three isomers.)

This was in the wild early days of organic chemistry, before there was any certain knowledge of what the structures of carbon compounds was really like, so Perkin didn't really know what he was doing; nobody did. Anyway, washing out the tars from his failed synthesis, Perkin found he was dissolving out a beautiful purple substance from the mess. Through tedious trial and error he came up with a reasonably reliable industrial synthesis: Perkin's mauve founded an entire industry, and purple fabrics were all the rage for a little bit.

Aniline and the toluidines were obtained at the time as byproducts from coal tar, so Perkin's mauve was the first of the "coal-tar dyes", or "aniline dyes", for within several years there'd be a host of new colorful organic dyes derived from aniline and other aromatic amines found in coal tar. But at the time, none of the 19th century chemists quite knew what mauve even was, not the least because the entire chemical industry was very new and the quality and purity of chemicals was uncertain and highly variable. Analysis of surviving samples of Perkin's mauve reveals a bewildering mixture of substances, all derivatives of a substituted phenazinium skeleton (q.v. https://www.nature.com/articles/s41598-017-07239-z) The safranin(e)s (q.v. https://en.wikipedia.org/wiki/Safranin) are another example of phenazinium dyes, enjoying wide use today. Perhaps you've done a Gram stain with phenosafranine.

Anyway, it'd be fun to replicate the synthesis of Perkin's mauve, but aniline and toluidine aren't fun substances; they're poisonous and carcinogenic, and not cheaply obtained.

~Alyx

Ralph is a good boi and belongs to @robinhearts