Electrophilic Cyanations. I. Synthesis of Thiocyanatoheteroarenes and Tosylheteroarenes from Mercaptoheteroarenes Using p-Toluenesulfonyl Cyanide
摘要:
Mercaptoheteroarenes (1) underwent electrophilic cyanation with p-toluenesulfonyl cyanide (TsCN) in THF in the presence of NaH to give the corresponding thiocyanatoheteroarenes (2) in moderate to good yields. In DMF, tosylheteroarenes (4) were formed by substitution with p-toluenesulfinate ion through thiocyanatoheteroarenes (2).
Aroylation of Fused Pyrimidines; Synthesis of 4-Aroylfuro[2,3-d]-, 4-Aroylthieno[2,3-d]-, and 4-Aroylisoxazolo[5,4-d]pyrimidines
摘要:
4-Aroylfuro[2,3-d]-(4), 4-aroylthieno[2,3-d]-(7 and 8), and 4-aroylisoxazolo[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 (1a). The fused aroylpyrimidines (4 and 7) were also synthesized by oxidative decyanation of alpha-phenylheteroareneacetonitriles (10 and 11).