Premium
Reversible chair ↔ skew conformational interconversion of 1,3,2‐dioxaphosphorinane ring in the solid state
Author(s) -
Ślepokura Katarzyna Anna
Publication year - 2016
Publication title -
acta crystallographica section b
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.604
H-Index - 33
ISSN - 2052-5206
DOI - 10.1107/s2052520615020259
Subject(s) - conformational isomerism , chemistry , ring (chemistry) , crystallography , skew , ring flip , cyclohexane conformation , phase transition , single crystal , ion , crystal structure , stereochemistry , molecule , hydrogen bond , physics , thermodynamics , organic chemistry , astronomy
β‐NH 4 [(MeO) 2 cDHAP] (where cDHAP is cyclic dihydroxyacetone phosphate) has been investigated by X‐ray crystallography in the temperature range 350–100 K. Three reversible single‐crystal‐to‐single‐crystal phase transitions have been examined and four phases (high‐, room‐, medium‐ and low‐temperature phase, HTP, RTP, MTP and LTP, respectively) have been structurally determined: HTP (at 350 K, P 2 1 / a , Z = 24), RTP (290 K, , Z = 12), MTP (205 K, P 2 1 / a , Z = 4) and LTP (100 K, , Z = 24). Various puckering modes of the 1,3,2‐dioxaphosphorinane ring of the organic cyclic phosphate anion have been revealed in the crystal: chair and skew . The chair ↔ skew ring flipping, which has been shown to take place during the phase transitions, results in various populations of skew and chair conformers in different phases. The flexibility in the coordination geometry of ammonium cations is considered to assist in the conformational flexibility of the dioxaphosphorinane ring.