Crystal structures of tris[1-oxopyridine-2-olato(1−)]silicon(IV) chloride chloroform-d 1 disolvate, tris[1-oxopyridine-2-olato(1−)]silicon(IV) chloride acetonitrile unquantified solvate, and fac-tris[1-oxopyridine-2-thiolato(1−)]silicon(IV) chloride chloroform-d 1 disolvate

The homoleptic triply-ligated cation in two silyl chloride salt solvates of 1-oxo-2-pyridinone is found to co-crystallize as a mixture of fac and mer isomers. A related silyl cation of 1-oxo-2-pyridinethione is found as the fac isomer.


Figure 1
The structures of the molecular components in (I), with displacement ellipsoids drawn at the 50% probability level. The minor components of the ligand disorders are not shown.

Figure 2
The molecular structure of the cation and the Cl À anion in (II), with displacement ellipsoids drawn at the 50% probability level. The minor components of the ligand disorders and the unmodeled solvent (see text) are not shown. Table 1 Selected bond lengths (Å ) for (I).  Selected bond lengths (Å ) for (II).
[Si(OPO) 3 ]ClÁxCH 3 CN (II): A solution of Me 3 Si(OPO) (0.183 g, 1.00 mmol) in 8 ml of CH 3 CN was added to a solution of Me 3 SiOSiCl 3 (98 mL, d = 1.14 g/ml, 0.50 mmol) in 4 ml of CH 3 CN. Me 3 SiOSi(OPO) 2 Cl is formed as an intermediate. Allowing the solution to stand undisturbed for one day resulted in precipitation of colorless crystals of (II) (0.090 g) which were isolated by filtration. Evidence for the presence of fac and mer isomers was given by the presence of closely spaced OPO resonances in the 13 C NMR spectrum in accord with those reported in the literature (Tacke, Willeke & Penka, 2001). The synthesis, isolation, and characterization of Me 3 SiOSi(OPO) 2 Cl will be reported elsewhere.
[Si(OPTO) 3 ]ClÁ2CDCl 3 (III): Crystals of (III) deposited from a solution of ( 1 -allyl) 2 Si(OPTO)Cl in CDCl 3 upon standing for one year at room temperature in the dark. The synthesis of ( 1 -allyl) 2 Si(OPTO)Cl will be published elsewhere.

Refinement
Crystal data, data collection and structure refinement details are summarized in  13.5133 (7), 13.5039 (7), 13.7752 (7) 6.8347 (7), 11.1232 (12), 13.1513 (14) 13.9483 (12) (II)]. The disorders were modeled by refining the nitrogen/carbon ratios in each of the specific sites while using a common variable for pairs of sites on the same ligand. Atoms at each of these sites were constrained to be isopositional and to have equivalent anisotropic displacement parameters. In (II) highly disordered solvent, located in two independent channels along [100], was unable to be modeled. Reflection contributions from this solvent were fixed and added to the calculated structure factors using the SQUEEZE (Spek, 2015) function of the PLATON program, which determined there to be 54 electrons in 225 Å 3 accounted for per unit cell (25 electrons in 109 Å 3 in one channel, and 29 electrons in 115 Å 3 in the other). Although the exact amount of solvent was unknown, the only solvent involved in the reaction was acetonitrile and both starting materials were confirmed by 1 H NMR to be unsolvated. Thus the structure is represented as an acetonitrile solvate of unknown amount. Because no solvent was included in the atom list or molecular formula for (II), all calculated quantities that derive from the molecular formula [e.g., F(000), density, molecular weight, etc.] are known to be incorrect.