Preparation and Guest Release Properties of Supramolecular 3-Chlorobenzo[b]thiophene Heterocyclic Host Complex

Abstract

Supramolecular 3-chlorobenzo[b]thiophene heterocyclic host complex composed of chiral (1R,2S)-2-amino-1,2-diphenylethanol was successfully prepared using 3-chlorobenzo[b]thiophene-2-carboxylic acid. Four types of guest n-alkyl alcohols could be stored in one-dimensional channel-like cavities composed of chiral 21-helical columnar network structures. The release properties of the guest alcohol changed depending on the length of the alkyl chain in the alcohol.

Chirality Switching in Optical Resolution of Mandelic Acid in C1–C4 Alcohols: Elucidation of Solvent Effects Based on X-ray Crystal Structures of Diastereomeric Salts

“…However, n -PrOH was desorbed at an ∼3 °C higher temperature than i -PrOH. The difference between the desorption temperatures corresponded well with the order of their respective boiling points at atmospheric pressure, whereas a positive correlation between the alcohol boiling point and guest desorption temperatures from the solvated crystals was not always observed . Such a trend was also observed with the C4 alcohols; desorption of t -BuOH mainly occurred at the lowest observed temperature (75–110 °C), followed by s -BuOH (85–115 °C), i -BuOH (88–120 °C), and n -BuOH (85–130 °C).…”

Tunability of guest release properties and crystal structures in a supramolecular benzothiophene heterocyclic host complex

“…A comparison of the crystal structures of I-IV and the previously reported IJ1R,2S)-1/3-chlorobenzoijb]thiophene-2carboxylic acid-supramolecular host complex 3 shows that the shapes and styles of the 2 1 -helical columns are similar. However, the packing arrangements of the helical columns are different in all complexes, especially when the guest molecule is MeOH.…”

“…In the previously reported IJ1R,2S)-1/3-chlorobenzoijb]thiophene-2-carboxylic acid-supramolecular benzothiophene host complex containing both 2-carboxylic acid and 3-chlorine groups, guests MeOH, EtOH, n-PrOH, and n-BuOH were released at ~113 °C (T), ~102 °C (T), ~97 °C (T), and ~85 °C (T), respectively. 3 The release temperatures of all guest alcohols I-IV were lower than those of IJ1R,2S)-1/3-chlorobenzoijb]thiophene-2-carboxylic acid-supramolecular host complexes. In particular, the release temperatures of MeOH, EtOH, and n-PrOH from I, II, and III were ~30 °C lower than those of the corresponding IJ1R,2S)-1/3-chlorobenzoijb]thiophene-2-carboxylic acid-supramolecular host complexes (which were close to 100 °C).…”

“…2 We have recently developed a solid-state supramolecular heterocyclic host complex composed of IJ1R,2S)-2-amino-1,2diphenylethanol ij(1R,2S)-1] and 3-chlorobenzoijb]thiophene-2carboxylic acid as the heterocyclic components. 3 Interestingly, the obtained complex has one-dimensional (1D) channellike cavities formed by the assembly of 2 1 -helical columnar hydrogen-and ionic-bonded network structures composed of (1R,2S)-1 and 3-chlorobenzoijb]thiophene-2-carboxylic acid. In these 1D channel-like cavities, four types of n-alkyl alcoholsmethanol (MeOH), ethanol (EtOH), n-propanol (n-PrOH), and n-butanol IJn-BuOH)-can be stored as guests.…”