Use of the curtius rearrangement of acryloyl azides in the synthesis of 3,5-disubstituted pyridines: mechanistic studies.
A series of disubstituted pyridine derivatives was synthesized from the corresponding acryloyl azides by acetic acid-promoted cycloaddition. This represents a novel and convenient synthetic approach to the symmetric 3,5-disubstituted pyridines. The nature of the substituent on the double bond and the utilized solvent were found to be crucial to the yield of pyridines. The reactivity of the acid-promoted cycloaddition increases with the presence of aryl groups, such as phenyl and pyridinyl. We also explored the comprehensive mechanism by the acid-promoted cycloaddition of (13)C-labeled cinnamoyl azide. The symmetric 3,5-disubstituted pyridines were synthesized from acryloyl azides by acetic acid-promoted trimolecular condensation.
Chuang
Ta-Hsien
TH
School of Pharmacy, China Medical University, Taichung, 40402, Taiwan, Republic of China. thchuang@mail.cmu.edu.tw
Chen
Yu-Chi
YC
Pola
Someshwar
S
D019342:Acetic Acid / Q000737:chemistry*; D001386:Azides / Q000737:chemistry*; D003500:Cyclization; D015394:Molecular Structure; D011725:Pyridines / Q000138:chemical synthesis* / Q000737:chemistry; D013237:Stereoisomerism
D001386:Azides; D011725:Pyridines; D019342:Acetic Acid