Exploitation of the Ugi 5-Center-4-Component Reaction (U-5C-4CR) for the Generation of Diverse Libraries of Polycyclic (Spiro)Compounds

Abstract

An Ugi multicomponent reaction with chiral cyclic amino acids, benzyl isocyanide and cyclic ketones (or acetone) has been exploited as key step for the generation of peptidomimetics. After a straightforward set of elaborations, the peptidomimetics were converted into polycyclic scaffolds displaying two orthogonally protected secondary amines. Libraries of compounds were obtained decorating the molecules through acylation/reductive amination reactions on these functional groups.

Anionic and neutral 2D indium metal–organic frameworks as catalysts for the Ugi one-pot multicomponent reaction

“…27,28 In particular, we have evaluated the Ugi organic transformation, 33,34 which involves the condensation among four substrates, in this case a carbonylderivate, an amine, a carboxylic acid, and an isocyanide to form α-aminoacyl amide derivatives, which are important in the pharmaceutical industry and fine chemistry to develop organic drug-like molecule libraries. [35][36][37] Out of the evaluated MOFs we found that those with a suitable ratio of acid and basic sites in their structure displayed the best catalytic performance. 27 Both, InPF-50, and -51, are formed by SBUs composed of only one metal cation, with accessible acid sites.…”

Study and application of graphene oxide in the synthesis of 2,3-disubstituted quinolinesviaa Povarov multicomponent reaction and subsequent oxidation

“…Nevertheless, GO-assisted one-pot multistep reactions have been seldom explored, 34 at least using organo-or metal-functionalized GO composites. 35 Building on our experience in the development of new synthetic methodologies using MCRs [36][37][38][39][40][41][42][43][44] and in one-pot multistep processes, 45,46 and inspired by the potential of MCRs involving the employment of an external oxidant, 47 we decided to study the GO-promoted Povarov multicomponent reaction between anilines, aldehydes and 2,3-dihydrofuran (DHF) that acts as dienophile to give tetrahydroquinolines (THQs) 1, and their subsequent oxidation to 2,3 disubstituted quinolines 2 (Scheme 1).…”

Visible-light photocatalytic metal-free multicomponent Ugi-like chemistry

“…This approach was very useful to enable two-step one-pot multicomponent reactions: after performing the photocatalytic Ugi-3CR, the reaction conditions were changed without any intermediate purification, to trigger a new transformation. 16 More in detail, the synthesis of secondary imides via the use of a cleavable isocyanide and an Ugi-3CR/deprotection/Mumm transacylation sequence were chosen as representative multi-step one-pot processes. Accordingly, the Ugi-3CR with 2,4-dimethoxybenzyl isocyanide 26 afforded tertiary imides with a general structure 27 (Scheme 2), which were converted in situ into secondary linear imides 28-29 (Scheme 2 and Fig.…”