Favero Laura B, Giuliano Barbara M, Melandri Sonia, Maris Assimo, Caminati Walther
Istituto per lo Studio dei Materiali Nanostrutturati ISMN, Sezione di Bologna, CNR, Via Gobetti 101, 40129 Bologna, Italy.
Chemistry. 2007;13(20):5833-7. doi: 10.1002/chem.200700076.
The millimeter-wave absorption and Fourier transform microwave spectra of five isotopologues of the 1:1 adduct of dimethoxymethane-water have been measured in supersonic expansions. Each rotational transition appears as a quintuplet, due to the internal rotation of the two methyl groups, which are nonequivalent in the adduct. The water moiety, linked asymmetrically to dimethoxymethane, behaves as a proton donor to one of its oxygen atoms and interferes with the internal rotation of the farther methyl group through a C...HO interaction. From the analysis of the observed splittings, the V(3) barriers to the internal rotation of the two methyl groups have been determined to be 6.83(8) and 6.19(8) kJ mol(-1). The hydrogen bond structural parameters have been determined, the O...HO and C...HO distances being 1.93(1) and 2.78(4) A, respectively.
