I 2 -catalyzed one-pot synthesis of benzofuro/thieno[2,3- b ]pyrrole motifs

Elevating pyrrole derivative synthesis: a three-component revolution

Pyrrole is an essential chemical with considerable relevance as a pharmaceutical framework for many biologically necessary medications. The growing demand for biologically active compounds calls for a simple one-pot method for generating novel pyrrole derivatives. Nots surprisingly, several multicomponent reactions (MCRs) aim to synthesize pyrrole derivatives. However, this review presents the three-component synthesis of pyrrole derivatives, highlighting the significance of multicomponent reaction in synthesizing eclectic multi-functionalised pyrrole covering the selected literature on the three-component synthesis of substituted pyrrole from 2016 to late 2023. Furthermore, this article classifies the reactions based on the starting material with functional groups involved in the pyrrole ring formation.

Domino Michael/Oxa-Michael Reactions of the Unsymmetric Double Michael Acceptor for Access to Bicyclic Furo[2,3-b]pyrrole

By creating an unsymmetric double Michael acceptor 1, we were able to synthesize the nonaromatic-fused bicyclic furo[2,3-b]pyrrole nucleus using a domino Michael/oxa-Michael reaction. Adopting benzoyl acetonitrile 2d (CN as the electron-withdrawing group) as a substrate, we discovered a (DHQ)2AQN-catalyzed method for high diastereo- and enantioselectivity of those products. The reaction path has been determined by isolating the reaction intermediates, and density functional theory calculations support these findings. Beyond providing a synthetic approach, this work illustrated the compounds' possible use in antitumor activity.

The role of halogen bonds in the catalytic mechanism of the iso-Nazarov cyclization reaction: a DFT study

With the continuous development of halogen bonds, halogen bond donors have been used as clean and efficient catalysts in organic reactions. In this work, with inorganic halides (I₂, IBr, ICl, and ICl₃) as catalysts and the iso-Nazarov cyclization as the benchmark reaction, we aim at investigating the role of the halogen bond in the catalytic mechanism. The halogen bond catalyzed iso-Nazarov cyclization reaction involves three steps: carbon-carbon coupling process, [1,2]-H shift process, and [1,4]-H shift process. The halogen-bonding interaction promotes the charge accumulation of the oxygen atom in the carbonyl group and decreases the activation energy of the reaction. The catalytic activity of the halogen bond donor is enhanced in the order of I₂ < IBr < ICl < ICl₃, and it could be predicted that the partial covalent interaction of the I⋯O halogen bond between the catalyst ICl₃ and the oxygen atom of the reactant may exhibit good catalytic activity in the experiments. In the [1,4]-H shift process, the two-step hydrogen bond/halogen bond co-catalyzed mechanism exhibits the lowest reaction energy barrier than the one-step water co-catalyzed proton transfer mechanism and the direct one.

Iodine catalyzed one-pot four component synthesis of coumarinyl phosphoramidates via sequential addition of reactants

An unprecedented synthetic route for the preparation of a library of novel coumarinyl phosphoramidate derivatives via iodine catalysed one-pot four component reactions of ethyl 4-bromo-3-oxo-alkanoate, sodium azide, trialkyl phosphites, and phenols in ethanol is reported.