The conformational analyses of 2‐amino‐N‐[2‐(dimethylphenoxy)ethyl]propan‐1‐ol derivatives in different environments

• Published in: Acta crystallographica. Section C, Crystal structure communications Crystal structure communications, 2020-07, Vol.76 (7), p.681-689
• Main Authors: Nitek, Wojciech, Kania, Agnieszka, Marona, Henryk, Waszkielewicz, Anna M., Żesławska, Ewa
• Format: Article
• Language: English
• Subjects: 2‐picolinic acid; aminoalkanol; Anions; anticonvulsant activity; Asymmetry; Cations; Chlorides; Crystal structure; Derivatives; Hydrogen; hydrogen bonding; Salts
• ISSN: 2053-2296; 0108-2701; 2053-2296; 1600-5759
• DOI: 10.1107/S2053229620008244

Four crystal structures of 2‐amino‐N‐(dimethylphenoxyethyl)propan‐1‐ol derivatives, characterized by X‐ray diffraction analysis, are reported. The free base (R,S)‐2‐amino‐N‐[2‐(2,3‐dimethylphenoxy)ethyl]propan‐1‐ol, C13H21NO2, 1, crystallizes in the space group P21/n, with two independent molecules in the asymmetric unit. The hydrochloride, (S)‐N‐[2‐(2,6‐dimethylphenoxy)ethyl]‐1‐hydroxypropan‐2‐aminium chloride, C13H22NO2+·Cl−, 2c, crystallizes in the space group P21, with one cation and one chloride anion in the asymmetric unit. The asymmetric unit of two salts of 2‐picolinic acid, namely, (R,S)‐N‐[2‐(2,3‐dimethylphenoxy)ethyl]‐1‐hydroxypropan‐2‐aminium pyridine‐2‐carboxylate, C13H22NO2+·C6H4NO2−, 1p, and (R)‐N‐[2‐(2,6‐dimethylphenoxy)ethyl]‐1‐hydroxypropan‐2‐aminium pyridine‐2‐carboxylate, C13H22NO2+·C6H4NO2−, 2p, consists of one cation and one 2‐picolinate anion. Salt 1p crystallizes in the triclinic centrosymmetric space group P, while salt 2p crystallizes in the space group P41212. The conformations of the amine fragments are contrasted and that of 2p is found to have an unusual antiperiplanar arrangement about the ether group. The crystal packing of 1 and 2c is dominated by hydrogen‐bonded chains, while the structures of the 2‐picolinate salts have hydrogen‐bonded rings as the major features. In both salts with 2‐picolinic acid, the specific R12(5) hydrogen‐bonding motif is observed. Structural studies have been enriched by the generation of fingerprint plots derived from Hirshfeld surfaces. Crystal structure analyses illustrate the conformational properties of 2‐amino‐N‐(dimethylphenoxyethyl)propan‐1‐ol derivatives due to different positions of a methyl substituent in the aromatic ring and the presence of a 2‐picolinate anion. The change of the methyl‐group position influences the geometry of the –O—C—C– linker with respect to the aromatic ring.