Aroylation of Fused Pyrimidines; Synthesis of 4-Aroylfuro[2,3-d]-, 4-Aroylthieno[2,3-d]-, and 4-Aroylisoxazolo[5,4-d]pyrimidines

4-Aroylfuro[2,3-dl-(4), 4-aroylthieno[2.3-dl-(7and S), and 4aroylisoxazolo[5.4-d]pyrimidines(13) were synthesized by aroylation of the fused chloro-(3a and 12) or bromopyrimidines (3b, 5, and 6) with arenecarbaldehydes (2) catalyzed by an imidazolium salt (la).The fused aroylpyrimidines (4 and 7) were also synthesized by oxidative decyanation of a-phenylheteroareneacetonitriles (10 and 11).