Highly Diastereoselective Synthesis of 4,5-dihydro-1H-imidazole Derivatives via Electro-Oxidative Formal [3+2] Cycloaddition

Das, Dipankar (2022) Highly Diastereoselective Synthesis of 4,5-dihydro-1H-imidazole Derivatives via Electro-Oxidative Formal [3+2] Cycloaddition. Masters thesis, Indian Institute of Science Education and Research Kolkata.

Text (MS dissertation of Dipankar Das (17MS022)) 17MS022_Thesis_file.pdf - Submitted Version Restricted to Repository staff only Download (10MB)

Abstract

4,5-dihydro-1H–imidazole scaffold is one important heterocyclic scaffold that has several medicinal importance as an antihypertension, antiprotozoal, anticancer drug, etc. This scaffold is not aromatic and is an intermediate redox state of imidazole. For that reason, it is pretty challenging to synthesize. There are different classical methods to prepare it, but we used electrochemistry to synthesize this moiety. We used two masked glycine derivatives as coupling partners to undergo electro-oxidative [3+2] cycloaddition to prepare cis- and trans-diastereomers of dihydroimidazole. We also found an inherent tendency of cis-isomer to convert to trans-isomer, which we efficiently accelerated in the presence of an inexpensive acid source. We also found a one-pot synthesis for fused pyrollo-imidazolium dione (bicyclic [3,3,0] system) efficiently using glycine derivatives and electrochemistry.

Actions (login required)

View Item