New pyrrolo[2,3-d]pyrimidines that have aryl groups at the 2-, 4-, and 6-positions were prepared by the arylation reaction of 4-chloro-7-methyl-2-(methylthio)-6-phenylpyrrolo[2,3-d]pyrimidine (6) and the corresponding arylboronic acid under Suzuki-Miyaura conditions followed by a second arylation under Liebeskind-Srogl cross-coupling conditions. A parallel study that began with the C-2 chemoselective arylation of 6 under Liebeskind-Srogl conditions followed by a Suzuki-Miyaura coupling at C-4 was carried out, and the results of each route were compared. All of the tranformations were performed under microwave irradiation.