2-(1,3-Oxazolin-2-yl)pyridine and 2,6-bis(1,3-oxazolin-2-yl) pyridine

The data presented in this article are related to research articles “Titanium and vanadium catalysts with oxazoline ligands for ethylene-norbornene (co)polymerization (Ochędzan-Siodłak et al., 2018). For the title compounds, 2-(1,3-oxazolin-2-yl)pyridine (Py-ox) and 2,6-bis(1,3-oxazolin-2-yl)pyridine (Py-box), the single-crystal X-ray diffraction measurement together with NMR, GC, MS, DSC analysis, like also the method of crystallization are presented.


Data
The presented compounds, 2-(1,3-oxazolin-2-yl)pyridine (Py-ox) and 2,6-bis(1,3-oxazolin-2-yl) pyridine (Py-box), are commonly applied as ligands for complexes with transition metals: cobalt [2], rhenium [3], platinum and palladium [4,5] for Py-ox, as well as copper [6,7], ruthenium [8][9][10][11], rhodium [12], manganese [13], silver [14], nickel [15], cobalt [16], terbium [17], and iron [18], in the case of Py-box. Some of them reveal catalytic properties. In our work, the Py-ox and Py-box compounds were applied as ligands for titanium and vanadium complexes, which turned out to be active in polymerization of ethylene and copolymerization of ethylene with norbornene [1]. The X-Ray information for Py-ox and Py-box compounds can be important for comparative studies, to show differences between these compounds not coordinated by metal atom and applied as ligands. It can help to understand dependence between the structure and activity of the designed complexes. The presented crystallization methods are worth to notice. The improved method of purification enable to obtain the studied compound of high quality.

Synthesis
The synthesis was performed mainly according to Stokes et al. [19]. The crude product was subjected to flash chromatography using the MeOH: AcOEt (1:4) mixture as eluent. Yield 60%. Elemental analysis C 8  The crystals were obtained at room temperature from highly anhydrous toluene/hexane mixture. The solvents were freshly distilled over sodium. The highly anhydrous conditions are crucial. All operations were performed in a glove-box filled with argon. Py-ox (20 mg) was placed in a 5 ml snap cap vial with plastic cap and dissolved in toluene (1 ml). Then, hexane (1 ml) was added and the solution was left to stand at room temperature for a week.

2,6-bis(1,3-oxazolin-2-yl)pyridine (Py-box)
The crystals of appropriate quality were obtained at room temperature from DMSO-d6 solution by long standing time in NMR tube. All operations were performed in a glove-box filled with argon. DMSO-d6 solvent from sealed glass ampoules was applied. Py-box (15 mg) and DMSO-d6 (0.6 ml) was placed in NMR tube and the cap was sealed by a parafilm. The solution was left to stand at room temperature for a month.

X-ray
The single-crystal X-ray diffraction experiments were performed at 293.0(1)K on the Xcalibur diffractometer, equipped with a CCD area detector and a graphite monochromator for the MoKα radiation. The reciprocal space was explored by ω scans with detector positions at 60 mm distance from the crystal. The diffraction data processing of studied compounds (Lorentz and polarization corrections were applied) were performed using the CrysAlis CCD [21,22]. Both structures Py-ox and Py-box were solved in the C2 and P2/n space group respectively, by direct methods and refined by a  Table 2.     full-matrix least-squares method using SHELXL14 program [23,24]. The H atoms were found based on geometrical parameters. In both structures H atoms were refined using a riding model. The structure drawings were prepared using SHELXTL and Mercury programs [25] (Figs. 1-3 and Tables 1,2

DSC
The melting temperatures were measured by differential scanning calorimetry DSC 2010 TA instrument calorimeter equipped with an automated sampler. The data were collected with the heat/ cool/heat cycle at a heating rate of 10°C/min under a nitrogen atmosphere (Figs. 12 and 13).

Transparency document. Supporting information
Transparency data associated with this article can be found in the online version at https://doi.org/ 10.1016/j.dib.2018.09.129.