In a recent paper by Gustafson et al. (DOI: 10.1021/acs.orglett.6b02650) the authors open with the argument that
aryl chlorides are both versatile synthetic handles and common functionalities in drug discovery.
However, they fail to give examples of current use in industry and pharmaceutical research.
I know of only one reaction that aryl chlorides are used for, and that would be the Ullmann biaryl (ether) coupling. Are there any other ones for which aryl chlorides are a good starting material? And then, about the second part of the sentence: Why are aryl chlorides a common functionality in drug discovery? Is it simply that compounds are chlorinated and then compared to their unchlorinated analogues?
All in all, please provide examples for the quoted statement above.