Electrons become chiral reagent in polymer synthesis

A chiral polymer has been made from entirely achiral monomers, simply by using a magnetic field to align the spin of the electrons involved in bond formation.

Creating large organic molecules as single mirror images is important in many fields of chemistry. ‘When you want to make drugs, for example, they have to be recognised by the body, [whose molecules have] one chirality – otherwise it can have catastrophic side effects’ says Ron Naaman at the Weizmann Institute of Science in Israel. Mechanisms that produce only one isomer are therefore highly valuable – for example, asymmetric organocatalysis was rewarded with the 2021 chemistry Nobel prize. However, Naaman says, even here ‘you have make the catalyst and separate it into the two chiralities before you can use it’.