Atroposelective Thermal Reactions of Axially Twisted Amides and Imides

Enantiomeric resolution by HPLC of axial chiral amides using amylose tris[(S)-1-phenylethylcarbamate]

“…3,5,6 Chiral amides were prepared by standard methods. 1 Solvents were either highperformance liquid chromatography (HPLC)-grade from Merck (Darmstadt, Germany) or Carlo Erba (Milan, Italy) or purified as usual. 7 Dead times (t 0 ) were estimated using 1,3,5-tri-tert-butylbenzene.…”

Photochemistry of Atropisomers: Non-biaryl Atropisomers for Stereospecific Phototransformations

“…10 Utilizing both cyclic and acyclic atropisomeric systems for radical reactions, they validated that the methodology is viable for asymmetric synthesis through axial chirality transfer. Segueing into photochemistry, Bach et al displayed the efficacy of utilizing axial chirality to influence intermolecular photochemical transformations (Scheme 2).…”

“…10 They cleverly took advantage of the fact that o-halo-acrylanilides 1, are not planar and exist in a twisted conformation in order to alleviate unfavorable steric interactions between the ortho-substituents of the phenyl ring and R 1 substituent (Scheme 1). 23 They established that radical cyclization reactions of o-halo-acrylanilides 1 led to oxindole products in high selectivities with complete transfer of axial chirality from the reactant to point chirality in the product.…”

Deracemization of Axially Chiral Nicotinamides by Dynamic Salt Formation with Enantiopure Dibenzoyltartaric Acid (DBTA)

“…An understanding of how to control the axial chirality of aromatic OPEN ACCESS amides is important, and this has received increasing attention over the past decades. The importance of these chiral elements has been exemplified in attractive asymmetric reactions leading to optically active materials, such as anilides [2][3][4][5][6], N-arylimides [7][8][9][10], benzamides [11][12][13][14][15] and naphthamides [16][17][18][19][20][21]. Among a series of aromatic amides, nicotinamide is important because it is an essential element of nicotinamide adenine dinucleotide (NAD) and nicotinamide adenine dinucleotide phosphate (NADP), which are known for their part in biomimetic asymmetric reduction and oxidation in NAD/NADH model systems.…”