82853-93-8Relevant academic research and scientific papers
Palladium-catalyzed regio- And stereoselective access to allyl ureas/carbamates: Facile synthesis of imidazolidinones and oxazepinones
Banerjee, Prabal,Saha, Debarshi,Taily, Irshad Maajid
, p. 6564 - 6570 (2020)
Typically, transition metal catalysis enforces the stereodefined outcome of a reaction. Here we disclose the palladium-catalyzed regio- and stereoselective access to allylic ureas/carbamates and their further exploitation to diverse cyclic structures under operationally simple reaction conditions. This protocol features palladium-catalyzed decarboxylative amidation of highly modular VECs with good to excellent yield, minimal waste production, wide substrate scope, and low catalyst loading. In follow-up chemistry, we demonstrated the debenzylation of vinylic imidazolidinones to N-hydroxycyclic ureas and regioselective derivatization towards the facile synthesis of halohydrins and oxiranes under mild reaction conditions in good to excellent yields. This journal is
Oxidative 1,4-diamination of dienes using simple urea derivatives
Anumandla, Devendar,Littlefield, Ryan,Jeffrey, Christopher S.
, p. 5112 - 5115 (2014)
Diamination of alkenes and dienes has found widespread use in the synthesis of biologically active target molecules. Although the 1,2-diamination of alkenes has been comprehensively explored, versatile methods that install higher order 1,n-diamine moieties (e.g., n = 3-5) are not broadly developed. Herein, we report the development of an oxidative 1,4-diamination of dienes. This method represents one of the scarce examples of exclusive regioselectivity for 1,4-diamination. The reaction is easy to perform, uses simple reagents, works with a variety of functionalized dienes, and provides unique heterocyclic products.
Vinylogous Aza-Michael Addition of Urea Derivatives with p-Quinone Methides Followed by Oxidative Dearomative Cyclization: Approach to Spiroimidazolidinone Derivatives
Kaur, Navpreet,Singh, Priyanka,Banerjee, Prabal
supporting information, p. 2813 - 2824 (2021/04/21)
Herein, we report an efficient protocol for the synthesis of spiro-imidazolidinone-cyclohexadienones from p-quinone methides (p-QMs) and dialkyloxy ureas under mild conditions. The strategy follows a two-step process involving an initial vinylogous conjugate addition of urea derivatives to p-QMs, followed by oxidative dearomative cyclization of open-chain product to the projected spiro-imidazolidinones. This protocol exhibits good functional group tolerance and provides a straightforward method to access spiro-imidazolidinone-cyclohexadienones. In follow-up chemistry, we have shown the debenzylation of spiroimidazolidinones to give N-hydroxycyclic ureas. (Figure presented.).
[3+3] Annulation via Ring Opening/Cyclization of Donor–Acceptor Cyclopropanes with (Un)symmetrical Ureas: A Quick Access to Highly Functionalized Tetrahydropyrimidinones
Taily, Irshad Maajid,Saha, Debarshi,Banerjee, Prabal
, p. 7804 - 7813 (2019/12/27)
A mild and straight-forward access to pharmacologically privileged tetrahydropyrimidinones exploiting readily available Donor–Acceptor cyclopropanes (DACs) is reported. This methodology involves the Lewis acid catalyzed synthesis of uriedo-malonates from (un)symmetrical ureas and DACs followed by I2-base mediated cyclization to their corresponding tetrahydropyrimidinones. The cyclization protocol involves nucleophilic attack of the nitrogen of urea on the newly generated electrophilic acceptor end of DAC. The post functionalization offered potential biologically active molecules.
Nitrous Oxide Promoted Pauson-Khand Cycloadditions
Ricker, J. David,Mohammadrezaei, Vahid,Crippen, Thomas J.,Zell, Austin M.,Geary, Laina M.
supporting information, p. 4556 - 4559 (2019/01/04)
A Pauson-Khand cycloaddition of alkynes, alkenes, and carbon monoxide promoted by cobalt carbonyl and nitrous oxide to furnish cyclopentenones is described. Preliminary mechanistic experiments suggest that nitrous oxide functions in a manner similar to th
