Corante

About this Author
DBL%20Hendrix%20small.png College chemistry, 1983

Derek Lowe The 2002 Model

Dbl%20new%20portrait%20B%26W.png After 10 years of blogging. . .

Derek Lowe, an Arkansan by birth, got his BA from Hendrix College and his PhD in organic chemistry from Duke before spending time in Germany on a Humboldt Fellowship on his post-doc. He's worked for several major pharmaceutical companies since 1989 on drug discovery projects against schizophrenia, Alzheimer's, diabetes, osteoporosis and other diseases. To contact Derek email him directly: derekb.lowe@gmail.com Twitter: Dereklowe

Chemistry and Drug Data: Drugbank
Emolecules
ChemSpider
Chempedia Lab
Synthetic Pages
Organic Chemistry Portal
PubChem
Not Voodoo
DailyMed
Druglib
Clinicaltrials.gov

Chemistry and Pharma Blogs:
Org Prep Daily
The Haystack
Kilomentor
A New Merck, Reviewed
Liberal Arts Chemistry
Electron Pusher
All Things Metathesis
C&E News Blogs
Chemiotics II
Chemical Space
Noel O'Blog
In Vivo Blog
Terra Sigilatta
BBSRC/Douglas Kell
ChemBark
Realizations in Biostatistics
Chemjobber
Pharmalot
ChemSpider Blog
Pharmagossip
Med-Chemist
Organic Chem - Education & Industry
Pharma Strategy Blog
No Name No Slogan
Practical Fragments
SimBioSys
The Curious Wavefunction
Natural Product Man
Fragment Literature
Chemistry World Blog
Synthetic Nature
Chemistry Blog
Synthesizing Ideas
Business|Bytes|Genes|Molecules
Eye on FDA
Chemical Forums
Depth-First
Symyx Blog
Sceptical Chymist
Lamentations on Chemistry
Computational Organic Chemistry
Mining Drugs
Henry Rzepa


Science Blogs and News:
Bad Science
The Loom
Uncertain Principles
Fierce Biotech
Blogs for Industry
Omics! Omics!
Young Female Scientist
Notional Slurry
Nobel Intent
SciTech Daily
Science Blog
FuturePundit
Aetiology
Gene Expression (I)
Gene Expression (II)
Sciencebase
Pharyngula
Adventures in Ethics and Science
Transterrestrial Musings
Slashdot Science
Cosmic Variance
Biology News Net


Medical Blogs
DB's Medical Rants
Science-Based Medicine
GruntDoc
Respectful Insolence
Diabetes Mine


Economics and Business
Marginal Revolution
The Volokh Conspiracy
Knowledge Problem


Politics / Current Events
Virginia Postrel
Instapundit
Belmont Club
Mickey Kaus


Belles Lettres
Uncouth Reflections
Arts and Letters Daily
In the Pipeline: Don't miss Derek Lowe's excellent commentary on drug discovery and the pharma industry in general at In the Pipeline

In the Pipeline

« Plenty of Tar to Go Around | Main | The FDA Loosens Its Tie »

January 13, 2006

How Not to Do It: Ether Peroxides

Email This Entry

Posted by Derek

We've had a few incidents recently at the Wonder Drug Factory where people have been using some common solvents like ether or tetrahydrofuran (THF) and ended up with odd results. When they check their reactions, there's something else in there that hasn't turned up before. The same impurity turns up in completely different reactions, too, which narrows the possibilities down a lot. In a couple of these cases, the chemists involved went to the trouble of isolating this pesky impurity and getting NMR spectra of it.


The experienced chemists in my audience are already cringing; I can feel it. No, we didn't blow anything up. But the people involved are now the proud owners of clean NMRs of ether peroxides. These explosive little beasts are an unavoidable byproduct of storing ethereal solvents where ambient oxygen can get to them. Oxygen is just too reactive - which is fine for us, biochemically, since that keeps us alive, but it can be a real nuisance in other situations.

These solvents are usually sold with some inhibitor added, a free-radical sponge like BHT, for example. But over time - or if someone in the supply chain stored things improperly - this will get used up, and then peroxidation moves right along. In extreme cases, such as with the unstoppable di-isopropyl ether, you can even get crystals of the peroxide coming out of solution. I have never seen this in person, and I will be very glad if I never do


Biologists and physicians have, among chemists anyway, a reputation for treating bottles of ether much more cavalierly than we do. A colleague of mine witnessed this at first hand at a former company of hers. A note had gone out to all the departments to check for old ether bottles, went into the possibility of crystal formation, and told everyone to notify the haz-mat team if any bottles were uncovered. In the molecular biology department where my source was working, one of the lab heads promptly marched out and rooted through the cabinets, emerging a few minutes later with a can of ether of uncertain age. This person then held the can up to his ear while shaking it, listening to see if any solid material was sloshing around in there. Which is one way to find out.

Comments (1) + TrackBacks (1) | Category: How Not to Do It


COMMENTS

1. robopox on January 16, 2006 12:19 PM writes...

To keep one's left-over varnish from reacting with oxygen, and "skinning over", it's common to fill the can's airspace from a small bottle of inert gas (sometimes argon, but often nitrogen).
And then quickly pound on the lid.

A recent suspect can of diethyl ether led to a 6 hour shut down of our community college science building.

Why not store ether with an inert blanket of gas?
Especially in the we-only-need-a-little-every-once-in-a-while
school stockrooms filled with OLD chemicals?

(omitting the "hammer on the lid" portion of the varnish protocol?

Permalink to Comment

TRACKBACKS

Listed below are links to weblogs that reference How Not to Do It: Ether Peroxides:

While I was in Palo Alto last week, there was an explosion in the Chemistry Dept. here. It happened in one of the organic synthesis groups so the natural first suspect was flammable organics...things like ether peroxides. But it seems that this explo... [Read More]

Tracked on January 18, 2006 8:59 PM


EMAIL THIS ENTRY TO A FRIEND

Email this entry to:

Your email address:

Message (optional):




RELATED ENTRIES
A Last Summer Day Off
The Early FDA
Drug Repurposing
The Smallest Drugs
Life Is Too Short For Some Journal Feeds
A New Look at Phenotypic Screening
Small Molecules - Really, Really Small
InterMune Bought