Sciencemadness Discussion Board

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Yttrium2 - 28-10-2021 at 18:19

What are some cheap, available tools that could be used for structure elucidation?

j_sum1 - 28-10-2021 at 19:17

Sounds to me like you are after an inexpensive structure elucidator.

As always, context is everything.

SWIM - 28-10-2021 at 22:16

Before we used all these modern machines it was still possible, but a lot harder.

large organic molecules would be broken down by various destructive means (pyrolysis, and reactions with various powerful reagent combinations that would break carbon bonds, or strip off certain functional groups) and the stuff produced would characterized by melting points and various analytical means. (much easier with these smaller bits of the original large molecule).

The idea being that if you break that molecule up a whole bunch of different ways you'll be able to identify what all sorts of pieces are and eventually work the whole thing out like a three dimensional crossword puzzle.

There's a book from the mid 20th century in the sciencemadness library, Something like, THE TECHNOLOGY AND CHEMISTRY OF ALKALOIDS.
It is mostly about extracting and purifying alkaloids on a large scale for commercial use, but it also discusses how the structure of each molecule was elucidated back in the days before modern electronics.


They did a lot of destructive distillation:
Destructive distillation under CO2
Distillation from soda-lime
Destructive distillation preceded by exhaustive methylation

Various kinds of hydrolysis were popular too.

It must have taken ages to find structures this way.