Asymmetric epoxidation

Benjamin List and co-workers have reported in JACS on their studies of cinchona alkaloid catalyzed asymmetric epoxidation of activated olefins.

JACS paper

Metabolomics

At some point I’m going to need to review principal component analysis to truly understand this metabolomics study that identified a small molecule phermone.

ACIE paper

Determination of stereochemistry on a small scale

Scptt Rychnovsky and co-workers have reported in JACS on a clever way to determine the stereochemical configuration of a primary amine by using mass spectrometry.  This may be useful when you only have a small amount of material.

JACS paper

Named reaction refresher

The Criegee rearrangement converts a tertiary alcohol into an alcohol and a ketone by using a peroxy acid and in turn forming peroxide intermediate that breaks down and forms the products.  In an ozonolysis, after the [3+2] between an ozone molecule and an alkene, the five membered ring breaks down to  a carbonyl and a carbonyl dioxide intermediate, which is called a “Criegee inermediate”.

Craig Taatjes and co-workers from Sandia National Laboratories have reported in Science on the observation of the Criegee intermediate by mass spec in the gas phase by reacting a methyl iodide radical and oxygen.

 

Science paper

TS analog complexed with protein and water

Vern Schramm and co-workers at Albert Einstein College of Medicine have reported in JACS on the observation of a complex between a transition state analog and an enzyme, methylthioadenosine/S-adenosylhomocysteine nucleosidase through mass spectrometry.

JACS paper

Evidence of iron-oxo

Miquel Costas and co-workers at Universitat de Girona in Spain have reported in Nature Chemistry on the observation of an iron-oxo complex using mass spectrometry.

Nature Chemistry paper