A Direct Approach to Orthogonally Protected α-Amino Aldehydes.

O-Neopentyl-xanthate 19 bearing a masked α-amino aldehyde, with the two functional groups orthogonally protected, reacts cleanly with many functional alkenes. The radical addition-transfer furnishes densely functionalized adducts that can be further transformed into an array of amino-substituted carbocycles and heteroaromatics. They are also easily converted into imidazolones.

Xanthate-Mediated Incorporation of Quaternary Centers into Heteroarenes.

The xanthate-mediated addition of tertiary alkyl radicals to heteroarenes enabled the easy functionalization of heteroaromatic rings as well as more decorated structures, such as marketed drugs or agrochemicals. This work provides a synthetic tool for efficiently exploring the chemical space by allowing late-stage diversification with a high tolerance toward functional groups.