An Expeditious Iodine-Catalyzed Synthesis of 3-Pyrrole-substituted 2-Azetidinones

Molecules

Debasish Bandyopadhyay¹  Jessica Cruz²  Ram N. Yadav¹ 

[1] id="af1-molecules-17-11570">Department of Chemistry, The University of Texas-Pan American, 1201 West University Drive, Edinburg, TX 78539, U

关键词: iodine;    microwave;    2-azetidinone;    pyrrole;    catalysis;    green synthesis;   

DOI  :  10.3390/molecules171011570

来源: mdpi

【 摘 要 】

2-Azetidinones and pyrroles are two highly important classes of molecules in organic and medicinal chemistry. A green and practical method for the synthesis of 3-pyrrole-substituted 2-azetidinones using catalytic amounts of molecular iodine under microwave irradiation has been developed. Following this method, a series of 3-pyrrole- substituted 2-azetidinones have been synthesized with a variety of substituents at N-1 and at C-4. The procedure is equally effective for mono- as well as polyaromatic groups at the N-1 position of the 2-azetidinone ring. The C-4 substituent has no influence either on the yield or the rate of the reaction. Optically pure 3-pyrrole-substituted 2-azetidinones have also been synthesized following this methodology. No deprotection/rearrangement has been identified in this process, even with highly acid sensitive group-containing substrates. A plausible mechanistic pathway has also been suggested based on the evidence obtained from ¹H-NMR spectroscopy. The extreme rapidity with excellent reaction yields is believed to be the result of a synergistic effect of the Lewis acid catalyst (molecular iodine) and microwave irradiation.

【 授权许可】

CC BY   
© 2012 by the authors; licensee MDPI, Basel, Switzerland.