| Abstract
| - Planar chiral dianthranilide (1) was resolved to enantiomers with use of (−)-(1S,4R)-camphanoylchloride as a chiral derivatizing agent. The (+)-1 enantiomer was assigned the S absoluteconfiguration from the X-ray crystal structure of its N,N‘-dicamphanoyl derivative. Optical resolutionof dithionodianthranilide (2) was accomplished by inclusion crystallization with (R,R)-1,2-diaminocyclohexane, and the X-ray structure of the corresponding adduct revealed the (−)-2stereoisomer has the R configuration. A slow boat-to-boat ring inversion (ΔG⧧ = 24.1 ± 0.1 kcalmol-1) causes racemization of (+)-1 in solution as manifested by a gradual decrease of the CDspectrum whereas, (−)-2 is configurationally stable at these conditions. The analysis of the CDspectra of the title compounds showed that the n−π* Cotton effect signs are determined by thehelicity of the skewed benzamide and thiobenzamide chromophores. The solid-state structures ofthe racemic and homochiral forms of 1 and 2 show different self-assembly patterns: the racemate(±)-1 prefers the cyclic R22(8) hydrogen bond motif, whereas the crystalline DMSO solvates of (±)-1and (+)-1 consist of 1D homochiral hydrogen-bonded assemblies generated by the C(6) motif. Inthe case of dithionolactams (±)-2 and (−)-2 two types of 1D networks were observed: in the racematethey are generated by the centrosymmetric R22(8) and R22(12) hydrogen bond motifs, whereas themolecules in the homochiral crystals are connected solely with use of the strongly nonplanar R22(8)motif.
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