Discovery of New Multi Component Reactions with Combinatorial Methods

Abstract

Abstract:The discovery of novel chemical reactions or reaction sequences that are able to generate useful chemical products may be regarded as the heart of organic chemistry. We present here concepts and methods on how to find and explore new multi component reactions, especially with automated combinatorial methods. This "combinatorial reaction finding" provides also a powerful tool to the understanding of the rules of organic chemistry, especially structure-reactivity relationships.

Synthesis of Functionalized Spiroheterocycles by Sequential Multicomponent Reaction/Metal-Catalyzed Carbocylizations from Simple β-Ketoesters and Amides

“…To this end, compounds 4f,g were easily cyclized with a comparable efficiency under standard conditions using Pd(OAc) 2 and PPh 3 in the presence of Et 3 N in refluxing CH 3 CN (entries 6, 7). 20 The expected spiro [6,4]lactams 7a,b conserved the feature of a synthetically useful exocyclic cis-fixed 1,3-diene which reacted with dimethyl acetylenedicarboxylate (DMAD) in refluxing benzene to give the tricyclic skeleton 8 with 93 % yield (Scheme 3).…”

“…Finally, bromoolefins 4h,i were subjected to the standard catalytic amidation conditions involving the system Pd(OAc) 2 c Heck reactions were performed in refluxing anhydrous CH3CN using 5 mol % of Pd(OAc)2 as catalyst.…”

“…Multicomponent reactions (MCRs), 1 combining at least three different substrates in a one-pot operation, constitute nowadays a central academic and industrial investigation domain 2 in diversity-oriented synthesis 3 of functionalized heterocycles. These very efficient atom-4 and step-economic 5 transformations also combine increase in molecular and functional complexity with practical and environmental concerns, 6 approaching quite closely the concept of an ideal synthesis.…”

Efficient synthesis of diarylidene octahydroacridines by one-pot multi-component tandem reactions

“…This methodology allows molecular complexity and diversity to be created by the facile formation of several new covalent bonds in a one-pot transformation quite closely approaching the concept of an ideal synthesis [1][2][3][4][5][6]. Microwave irradiation assisted organic synthesis is an increasingly popular field as indicated by numerous publications in the past years that have testified to the several advantages, such as enhancing reaction rates and increasing in yields under milder conditions [7,8].…”

New environmentally benign protocol for the synthesis of 3,4-dihydropyrimidin-2(1H)-ones: Practical access to mitotic kinesin EG5 inhibitor Monastrol

“…MCR condensations involve three or more compounds reacting in a single event, but consecutively to form a new product, which contains the essential parts of all the starting materials. The search and discovery for new MCR's on one hand, 3 and the full exploitation of already known multicomponent reactions on the other hand, is therefore of considerable current interest. One such MCR that belongs in the latter category is the venerable Biginelli dihydropyrimidine synthesis.…”