Simple synthesis makes curious chiral clamshell molecule

A class of molecules that look like open scallop shells has been made by French researchers.¹ This is the first time these curious compounds, whose chirality comes from hindered rotation around two bonds, have been synthesised in a single straightforward reaction. Most chiral chemicals are handed because they have four different groups bound to one carbon atom. However, there are other, stranger forms of chirality, such as atropisomerism. Here, steric strain hinders or stops rotation around a bond, creating a chiral axis and two mirror image molecules. This often happens in all-ortho substituted benzenes, in which the bond between the rings is the chiral axis.