297771-20-1Relevant articles and documents
An exploration into the amide-pseudo amide hydrogen bonding synthon between a new coformer with two primary amide groups and theophylline
Markad, Datta,Mandal, Sanjay K.
, p. 7112 - 7124 (2017)
A cocrystal between a new coformer with two primary amide groups, 2,2′-((1,4-phenylenebis(methylene))-bis((pyridin-2-ylmethyl)azanediyl))diacetamide (2-BPXG), and theophylline (THP) was selected as a model system to (a) demonstrate the presence of a rare amide-pseudo amide hydrogen bonding synthon in it and identify further the structural features by single crystal X-ray diffraction, and (b) establish its relevant physicochemical properties through a comparison with the coformer by Fourier-transform infrared (FT-IR) spectroscopy, differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), differential thermal analysis (DTA), powder X-ray diffraction (PXRD), and hot stage microscopy (HSM). To the best of our knowledge, this is the first example where a coformer with two primary amide groups has been used to form the amide-pseudo amide hydrogen bonding synthon. The co-crystal (2-BPXG·4THP) crystallizes in the triclinic space group P1 with Z = 1, where the unit cell contains one 2-BPXG molecule and four THP molecules. Meanwhile, the coformer 2-BPXG crystallizes in the monoclinic space group P21/c with Z = 2 (the asymmetric unit contains half of the molecule). Surprisingly, only 2-BPXG (compared to other coformers with aliphatic spacers between the two alkyl nitrogen atoms), which does not form the amide-amide hydrogen bonding synthon within itself, paves the way for the formation of the amide-pseudo amide hydrogen bonding synthon R22(9) with THP. An overall 2D supramolecular network is formed in 2-BPXG through the interlinking of ladder-shaped layers (which are generated through strong hydrogen bonding between one of the N-H bonds and pyridine nitrogen) via strong hydrogen bonding between the other N-H bond and the carbonyl group of an adjacent molecule. On the other hand, the coformer with one primary amide group on each end generates a ladder-shaped layer in the cocrystal through hydrogen bonding interactions with THP molecules. These ladder-shaped layers are further connected via strong π-π (centroid to centroid distance: 3.68 ?) and weak C-H?O interactions between the THP molecules to form an overall 3D supramolecular network in the cocrystal. Hydrogen bond propensities, Hirshfeld surface analysis and quantitative crystal structure analysis of both coformer and cocrystal allowed us to understand the amide-pseudo amide hydrogen bonding synthon in detail.
A general one-step synthesis of multidentate (pyridylalkyl)amines from mono-, bis-, tris- and tetrakis(bromomethyl)benzenes: Potential ligands for supramolecular assembly
Sengupta, Parbati,Henkes, Amanda E.,Kumar, Mananjali K.,Zhang, Hongming,Son, David Y.
, p. 79 - 86 (2008/09/20)
The synthesis of new multidentate nitrogen-containing ligands is of ongoing interest. In this report, the one-step syntheses of a series of (pyridylalkyl)amine derivatives is described. The reported compounds contain both pyridine rings and sp3-hybridized nitrogen as potential donor sites. The general synthetic method involves a room temperature reaction of mono-, bis-, tris-, or tetrakis(bromomethyl)benzenes with an excess of (pyridylmethyl)amine in tetrahydrofuran. The products can be purified by distillation, chromatography or recrystallization and are obtained in fair to good yields. The advantages of this synthetic method are the procedural simplicity and the ready availability of the starting materials. The applicability of these compounds in supramolecular chemistry is demonstrated by the reaction of two of the described ligands with silver(I) salts. Georg Thieme Verlag Stuttgart.
