Several synthetic techniques are available for the preparation of halogen-bonded adducts, including traditional solvent-evaporation methods and mechanochemistry. With the intention of reducing solvent usage and experimental times, we establish cosublimation as a synthetic technique for preparing halogen-bonded cocrystals, focusing on the C–I···N motif involving nitrogen-containing heterocycles. We selected four common halogen-bond donors (I2, 1,4-diiodobenzene, 1,4-diiodotetrafluorobenzene, 1,3,5-trifluoro-2,4,6-triiodobenzene) and four halogen-bond acceptors (2,3,5,6-tetramethylpyrazine, 1,4-diazabicyclo[2.2.2]­octane, 2,2′-bipyridyl, 1-adamantanecarbonitrile), by virtue of their range in volatility, and explored all 16 combinations via the following methods: solvent evaporation, overnight cosublimation in a sealed glass tube using a two-zone furnace, and expedited cosublimation in a vacuum sublimation apparatus. We show that the raw crystals obtained from overnight cosublimation are of suitable quality for single-crystal X-ray diffraction, resulting in five new crystal structures, two of which are, currently, unobtainable through other methods. Of these new structures, the first halogen bond to the nitrile group of 1-adamantanecarbonitrile is reported, resulting in the formation of a supramolecular rotor in a spinning top configuration as evidenced by 13C and 15N solid-state NMR spectroscopy. Strikingly, the cosublimation approach overcomes an anticooperative halogen-bonding effect to produce fully saturated cocrystals of the tritopic halogen bond donor 1,3,5-trifluoro-2,4,6-triiodobenzene with 1,4-diazabicyclo[2.2.2]­octane. Finally, we show that cosublimation can be used to rapidly prepare and purify bulk samples using a vacuum sublimation apparatus, enabling the scalable preparation of halogen-bonded cocrystals within 10 to 30 min using common laboratory equipment. The methods described here enable a broad exploration of the polymorphic landscape and may be extended to the facile preparation of other classes of cocrystals.

Halogen bonding is a noncovalent interaction between the electrophilic region of a halogen (σ-hole) and an electron donor. We report a crystallographic and structural analysis of halogen-bonded compounds by applying a combined X-ray diffraction (XRD) and solid-state nuclear magnetic resonance (SSNMR) approach. Single-crystal XRD was first used to characterize the halogen-bonded cocrystals formed between two fluorinated halogen-bond donors (1,4-diiodotetrafluorobenzene and 1,3,5-trifluoro-2,4,6-triiodobenzene) and several nitrogen-containing heterocycles (acridine, 1,10-phenanthroline, 2,3,5,6-tetramethylpyrazine, and hexamethylenetetramine). New structures are reported for the following three cocrystals, all in the P2/c space group: acridine-1,3,5-trifluoro-2,4,6-triiodobenzene (1/1), CFI·CHN, 1,10-phenanthroline-1,3,5-trifluoro-2,4,6-triiodobenzene (1/1), CFI·CHN, and 2,3,5,6-tetramethylpyrazine-1,3,5-trifluoro-2,4,6-triiodobenzene (1/1), CFI·CHN. C andF solid-state magic-angle spinning (MAS) NMR is shown to be a convenient method to characterize the structural features of the halogen-bond donor and acceptor, with chemical shifts attributable to cocrystal formation observed in the spectra of both nuclides. Cross polarization (CP) from F toC results in improved spectral sensitivity in characterizing the perfluorinated halogen-bond donor when compared to conventional H CP. Gauge-including projector-augmented wave density functional theory (GIPAW DFT) calculations of magnetic shielding constants, along with optimization of the XRD structures, provide a final set of structures in best agreement with the experimentalC and F chemical shifts. Data for carbons bonded to iodine remain outliers due to well-known relativistic effects.

for assisting with the recruitment of participants and data collection. The authors would also like to thank, Maryse Deraiche, Stéphane Bergeron, and Christyne Simard for their involment as patient partner. SB is supported by a Tier I Canada Research Chair in clinical cyberpsychology at UQO. AB, and PB are recipients of salary awards from the Fonds de recherche du Québec-Santé (FRQ-S). JB is supported by a Tier II Canada Research Chair in Physical Activity Promotion for Cancer Prevention and Survivorship.

IntroductionAfter metabolic and bariatric surgery (MBS), many patients have excess skin (ES), which can cause inconveniences. Identifying factors related to ES quantity and inconveniences is crucial to inform interventions. The aim of this study was to identify sociodemographic, physical, psychosocial, and behavioral factors associated with ES quantity and inconveniences.MethodsA mixed-method study with a sequential explanatory design was conducted with 124 adults (92% women, Mage46.5±9.9 years, Mtimepost-MBS34.2±27.6 months). During Phase I, ES quantity (arms, abdomen, thighs) and inconveniences, sociodemographic, anthropometric, clinical and behavioral outcomes were assessed. In Phase II, 7 focus groups were performed with 37 participants from Phase I. A triangulation protocol was completed to identify convergences, complementarities, and dissonances from quantitative and qualitative data.ResultsQuantitative data indicate only ES quantity on arms was associated with ES inconveniences on arms (r=.36, p<.01). Total ES quantity was associated with maximal body mass index (BMI) reached pre-MBS (r=.48, p<.05) and current BMI (r=.35, p<.05). Greater ES inconveniences was associated with higher social physique anxiety and age (R2=.50, p<.01). Qualitative data were summarized into 4 themes: psychosocial experiences living with ES, physical ailments due to ES, essential support and unmet needs, and beliefs of ES quantity causes.ConclusionsMeasured ES quantity is related to higher BMI, but not reported inconveniences. Greater self-reported ES quantity and inconveniences were associated with body image concerns.