Dataset Information

A crystalline sponge based on dispersive forces suitable for X-ray structure determination of included molecular guests.

ABSTRACT: A crystalline porous material showing one-dimensional (1-D) rectangular micropores (12 × 9 Å2) has been assembled from a semirigid macrocyclic tetraimine and EtOAc as the templating agent. The 1-D nature of the material is intrinsic to the conformationally rigid structure of a macrocyclic sub-unit bearing four cyclohexylidene residues. The multiple dispersive forces established among the aliphatic residues glutted the 1-D channels and provided thermal stability to the material at temperatures below 160 °C. Upon removal of the template, the structure of the empty solid exhibited permanent microporosity (SBET = 342 m2 g-1). Being a true molecular sponge, the channel framework of this material allowed the inclusion of a variety of molecular sample guests without compromising its crystalline nature. Remarkably, this crystalline material enabled the structure determination by X-ray diffraction of the included molecules. Theoretical studies demonstrated the vital role played by the dispersive forces in the overall stabilization of the crystal packing.

SUBMITTER: Sanna E

PROVIDER: S-EPMC5505123 | biostudies-literature | 2015 Oct

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

A crystalline sponge based on dispersive forces suitable for X-ray structure determination of included molecular guests.

Sanna Elena E Escudero-Adán Eduardo C EC Bauzá Antonio A Ballester Pablo P Frontera Antonio A Rotger Carmen C Costa Antonio A

Chemical science 20150714 10

A crystalline porous material showing one-dimensional (1-D) rectangular micropores (12 × 9 Å<sup>2</sup>) has been assembled from a semirigid macrocyclic tetraimine and EtOAc as the templating agent. The 1-D nature of the material is intrinsic to the conformationally rigid structure of a macrocyclic sub-unit bearing four cyclohexylidene residues. The multiple dispersive forces established among the aliphatic residues glutted the 1-D channels and provided thermal stability to the material at temp ...[more]

PMID: 28757946

Similar Datasets

Project description:Crystalline sponges are porous metal complexes that can absorb and orient common organic molecules in their pores and make them observable by conventional X-ray structure analysis (crystalline sponge method). In this study, all of the steps in the crystalline sponge method, including sponge crystal preparation, pore-solvent exchange, guest soaking, data collection and crystallographic analysis, are carefully examined and thoroughly optimized to provide reliable and meaningful chemical information as chemical crystallography. Major improvements in the method have been made in the guest-soaking and data-collection steps. In the soaking step, obtaining a high site occupancy of the guest is particularly important, and dominant parameters for guest soaking (e.g. temperature, time, concentration, solvents) therefore have to be optimized for every sample compound. When standard conditions do not work, a high-throughput method is useful for efficiently optimizing the soaking conditions. The X-ray experiments are also carefully re-examined. Significant improvement of the guest data quality is achieved by complete data collection at high angle regions. The appropriate disorder treatment of the most flexible ZnI2 portions of the host framework and refinement of the solvents filling the remaining void are also particularly important for obtaining better data quality. A benchmark test for the crystalline sponge method toward an achiral molecule is proposed with a guaiazulene guest, in which the guest structure (with ??100% site occupancy) is refined without applying any restraints or constraints. The obtained data quality with R int = 0.0279 and R 1 = 0.0379 is comparable with that of current conventional crystallographic analysis for small molecules. Another benchmark test for this method toward a chiral molecule is also proposed with a santonin guest. The crystallographic data obtained [R int = 0.0421, R 1 = 0.0312, Flack (Parsons) = -0.0071?(11)] represents the potential ability of this method for reliable absolute structure determination.

Dataset Information

A crystalline sponge based on dispersive forces suitable for X-ray structure determination of included molecular guests.

Publications

A crystalline sponge based on dispersive forces suitable for X-ray structure determination of included molecular guests.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets