Posts Tagged ‘Mauveine’

The history of Alizarin (and madder).

Thursday, October 18th, 2018

The Royal Society of Chemistry historical group (of which I am a member) organises two or three one day meetings a year. Yesterday the October meeting covered (amongst other themes) the fascinating history of madder and its approximately synthetic equivalent alizarin. Here I add a little to the talk given by Alan Dronsfield on the synthesis of alizarin and the impact this had on the entire industry.


The colour of purple is … not orange but mauve?

Wednesday, October 26th, 2011

My previous post on the topic of mauveine left the outcome dangling. Put simply, λmax is measured at about 549nm for mauveine A, but was calculated at about 440nm using a modern method for predicting colour (TD-DFT). According to the colour table below, that would make it orange, not mauve. Can the theoretical prediction be out by 110nm, or might it be the structure of the molecule itself that has been wrongly described?
colour table


The colour of purple

Thursday, February 24th, 2011

One of my chemical heroes is William Perkin, who in 1856 famously (and accidentally) made the dye mauveine as an 18 year old whilst a student of August von Hofmann, the founder of the Royal College of Chemistry (at what is now  Imperial College London). Perkin went on to found the British synthetic dyestuffs and perfumeries industries. The photo below shows Charles Rees, who was for many years the Hofmann professor of organic chemistry at the very same institute as Perkin and Hofmann himself, wearing his mauveine tie. A colleague, who is about to give a talk on mauveine, asked if I knew why it was, well so very mauve. It is a tad bright for today’s tastes!