Study of asymmetric aldol and Mannich reactions catalyzed by proline–thiourea host–guest complexes in nonpolar solvents

l‐Proline‐functionalized Fe3O4 nanoparticles as a novel magnetic chiral catalyst for the direct asymmetric Mannich reaction

“…Recently, the three‐component condensation of aldehydes, amines and ketones has gained popularity. A variety of catalysts such as Zn(OTf) 2 , H 3 PW 12 O 40 , ZrOCl 2 ⋅8H 2 O, ( S )‐serine, dodecylbenzenesulfonic acid, 1,1,3,3‐tetramethylguanidine, proline–thiourea, HClO 4 –SiO 2 and silica sulfuric acid have been utilized for three‐component synthesis of β‐amino carbonyl compounds. A powerful way of catalysing the direct asymmetric Mannich reaction is the use of proline and proline derivatives as catalysts .…”

Development of a syn‐Selective Mannich Reaction of Aldehydes with Propargylic Imines by Dual Catalysis: Asymmetric Synthesis of Functionalized Propargylic Amines

“…On the other hand, C6 alone (entry 17) wasu nable to catalyzet he reaction and unaltered startingm aterials were recovered after two days of stirring at room temperature. Next, we wondered whether an achiral bifunctional cocatalyst [22] could produce as imilar improvement, since literature precedentsi nthis matter were not fully supportive. Although the rate enhancement of ap roline-catalyzed Mannich reactiono fa na ctivated N-Boc imine by action of achiral bifunctionalc ocatalyst is reported, [22a] previous studies indicated that such achiral additives did not improve the reaction stereoselectivity,p articularly syn/anti selectivity.…”

Asymmetric Supramolecular Organocatalysis: A Complementary Upgrade to Organocatalysis

“…Within a year, Basceken and Demir described a proline/thiourea complex as a good supramolecular organocatalyst system for asymmetric LLB‐A reaction with high stereoselectivities under optimal conditions . The authors reported the synthesis of two types of bipyridine‐derived achiral thioureas and their application as co‐catalysts in proline‐catalyzed asymmetric LLB‐A reaction.…”

“…Basceken's approach involving l ‐proline ( 7a ) and bipyridine‐derived thiourea 20d as a supramolecular organocatalyst system for asymmetric LLB‐A reaction. Reprinted from ref . with permission from Elsevier.…”

“…The Mannich reaction, in which three components – namely, two carbonyl compounds and an amine – react to form a β‐amino carbonyl compound, is a very recognizable and highly useful transformation for the construction of nitrogenous compounds . In 2013, Demir and Basceken disclosed a good catalyst system [namely, a self‐assembled catalytic system based on l ‐proline ( 7a ) and bipyridine‐derived achiral thiourea 20d ] for asymmetric List–Barbas–Mannich (LBM) reactions and obtained high stereoselectivities under optimal conditions (Scheme ) …”