Adducts of alcohols with ethers: the rotational spectrum of isopropanol-dimethyl ether

The rotational spectra of three isotopologues of the isopropanol-dimethyl ether molecular complex have been measured with pulsed jet Fourier transform microwave spectroscopy. In the complex, isopropanol acts as a proton donor and takes a gauche conformation. The H → D isotopic substitution of the hydroxylic hydrogen participating in the O-H···O hydrogen bond produces an increase of the B and C rotational constants, according to the shrinkage of the O···O distance of about 7 mÅ, underlying and sizing the associated Ubbelohde effect.