Synthesis of (Z)-2-(2H-Isoquinolin-1-ylidene)acetamides by Iodine-Mediated Cyclization of (Z)-3-Amino-3-(2-vinylphenyl)propenamides

Abstract

(Z)-2-(2-Acetyl-2H-isoquinolin-1-ylidene)acetamides have been synthesized from 2-vinylbenzonitrile derivatives in three steps. The key step involves the iodine-mediated 6-endo cyclization of (Z)-3-acetylamino-3-(2-vinylphenyl)propenamides, which are prepared by the coupling of 2-vinylbenzonitriles with magnesium enolates of tertiary amides followed by N-acetylation.

6-endo cyclization - iodine - isoquinoline - magnesium amide - magnesium enolate

References

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