We studied different haloarenes, haloheteroarenes and dihalobenzenes with Ph3Sn− ions in DMSO or acetonitrile (CH3CN) as solvents, in the dark or under irradiation to determine whether the halogen metal exchange (HME) reaction or the SRN1 process prevails. With p- chloroanisole the photostimulated reaction is sluggish in DMSO. There is an HME reaction with 2-and 3-chlorothiophene. Bromoarenes (p-bromoanisole, p-dibromobenzene and 1- ...