Structural Implications of C−H···S Contacts in Organophosphorus Compounds. Studies of 1,6-Anhydro-2-O-tosyl-4-S- (5,5-dimethyl-2-thioxa-1,3,2-dioxaphosphorinan-2-yl)-β-d-glucopyranose by X-ray and Solid-State NMR Methods

1,6-Anhydro-2-O-tosyl-4-S-(5,5-dimethyl-2-thioxa-1,3,2-dioxaphosphorinan-2-yl)-β-d-glucopyranose (1, C₁₈H₂₅O₈PS₃), crystallized from polar and/or nonpolar solvents, forms different modifications in the solid phase. Crystal structures of 1 (obtained from a methanol solution) and its 2-propanol solvate (1a) were established by X-ray structure analysis at low temperature. One-component crystal 1 is orthorhombic, space group P2₁2₁2₁, with a = 7.483(4) Å, b = 11.156 (6) Å, c = 27.11(2) Å, V = 2263 (2) ų, Z = 4, and D_c = 1.457 g cm^-3. Refinement of 275 parameters using 2661 observed reflections (I > 2σ(I)) converged at R(F) = 0.0372. The crystal of 1a is an inclusion structure containing molecules of 1 and 2-propanol in the ratio 1/1; crystals are triclinic, space group P1, with a = 9.637(6) Å, b = 9.709(6) Å, c = 8.865(8) Å, α = 110.27(5)°, β = 106.33(5)°, γ = 108.70(6)°, V = 661.3(8) ų, Z = 1, and D_c = 1.398 g cm^-3. Full-matrix least-squares refinement of 307 parameters using 2478 observed reflections gave final R(F) = 0.0349. Intermolecular hydrogen bonds (O−H···O, C−H···O in 1; O−H···O, O−H···S in 1a) are present along with the C−H···SP intermolecular interactions. A search of Cambridge Structural Database shows that such contacts are not unusual for organothiophosphoryl compounds. The solid-state structures were studied by the NMR spectroscopy. The analysis of the ³¹P chemical shift parameters enabled the correlation of the δ₃₃ principal element of chemical shift tensor and span (Ω) with C−H···SP contact. The presence of toluene-d₈ in the crystal lattice of inclusion complex 1b was confirmed by ²H NMR spectroscopy.