Complexity catalogs | Opinion

If you are an organic chemist, you almost certainly order reagents and intermediates from supplier catalogs. There are many, from large generalist companies that offer a bit of everything, to “constituent” companies with huge inventories of small molecules with built-in functional handles, to small shops specializing in a particular type of reagent (or a particular type of chemistry that allows them to make interesting compounds to sell).

It has not always been so. There is a long out of print memoir memorably titled Excuse me sir, would you like to buy a kilo of isopropyl bromide, written by a certain Max Gergel. He founded Columbia Organic Chemicals in the 1940s, when what is now called the fine chemical business was much smaller, and his book is an entertaining look at the old days of custom manufacturing. His tales will raise eyebrows until they meet the hairline; it was a tough business. Over the decades and the expansion of the market, things have become slightly more genteel.

When ordering a compound or reagent, it can be difficult, if not impossible, to know where it actually came from

But it’s still an interesting landscape. There are broadly three types of vendors: a few smaller ones who manufacture almost every item in their catalog; the larger ones who make some of their own stock and outsource the rest to others, or buy it on the open market; and those who do nothing with their own hands. Some of the latter just resell stuff they’ve lined up obscure stocks of, and some have big catalogs but no warehouses at all. This group will immediately order anything you ask for while they try to find someone to make the product!

Complications become apparent. When ordering a compound or reagent, it can be difficult, if not impossible, to tell where it actually came from. An extreme example is an alkaloid called sparteine, which is used in small amounts in chiral synthesis. It looks like someone isolated a very large batch of it for some reason (maybe about 20 or 25 years ago) and almost all commercial sparteine ​​since then can be traced back to that same drum, sold and resold catalog after catalog. In the end, there were few and it turned out that no one made it at all!

Today, most industrial chemicals can be traced back to producers in China and India. If you are manufacturing a new compound on a large scale (a newly approved pharmaceutical product, for example), you will need to pay close attention to your supply chain. Finding reliable suppliers and locking them into production contracts is a specialized skill, and the people who do this do not reveal their secrets. There may be multiple layers to the problem: Intermediate A requires five steps to produce, and one of those steps requires Reagent B, which is actually only made by two facilities in southern China, both of which depend on a by-product stream thrown away by another factory downstream that makes something else.

Finding reliable suppliers and locking them into production contracts is a specialized skill, and the people who do this do not reveal their secrets.

World events can change all that. The pandemic has, at various times, deeply disrupted supply chains in China and India, of course. Economic shocks have also hit – for example the solvent acetonitrile has over the years become mostly a by-product of factories making acrylonitrile for the plastics industry, which itself goes up and down with car production . While demand for new cars has dried up, acetonitrile has also tended to become significantly more expensive. The war in Ukraine has affected a very vibrant and useful industry there – providing unique basic intermediates for pharmaceutical drug discovery, as well as many external synthetic organic chemistry contracts.

The world of chemical supply is therefore far from straightforward and can be affected in unpredictable ways. The past two years have illustrated some of this, leading to attempts to make supply chains more robust. But it’s not a cheap, fast process (how long does it take to build a new fine chemical plant, and where are you going to put it?) Ultimately, it’s a global business and will always be vulnerable to global concerns – many of which we have these days…

Sharon D. Cole