A general synthesis of substituted formylpyrroles from ketones and 4-formyloxazole.
A novel two-step synthesis of substituted 2-formylpyrroles is described. Aldol adducts of ketones and 4-formyloxazole undergo a dehydration/oxazole hydrolysis/cyclization cascade on sequential treatment with MsCl/Et3N and aqueous NaOH to yield 5-substituted and 4,5-disubstituted 2-formylpyrroles. The methodology was extended to an N-benzyl thiazolium salt.
Reeves
Jonathan T
JT
Department of Chemical Development, Boehringer Ingelheim Pharmaceuticals Inc, Ridgefield, CT 06877-0368, USA. jreeves@rdg.boehringer-ingelheim.com
Song
Jinhua J
JJ
Tan
Zhulin
Z
Lee
Heewon
H
Yee
Nathan K
NK
Senanayake
Chris H
CH
D005561:Formates / Q000737:chemistry*; D006900:Hydroxylation; D007659:Ketones / Q000737:chemistry*; D015394:Molecular Structure; D010080:Oxazoles / Q000737:chemistry*; D011758:Pyrroles / Q000138:chemical synthesis / Q000737:chemistry*
C520454:4-formyloxazole; D005561:Formates; D007659:Ketones; D010080:Oxazoles; D011758:Pyrroles; C030544:formic acid