Knowledge Bank

Microwave spectra have been measured for the most abundant isotopic species of two van der Waals complexes of 3-hydroxytetrahydrofuran: 3-hydroxytetrahydrofuran-$H2O$ and 3-hydroxytetrahydrofuran-Ar. For the $H2O$ complex the fitted rotational constants suggest that the water molecule forms a double hydrogen bond with the furan by donating a hydrogen bond to the ring oxygen and accepting a hydrogen bond from the hydroxyl group. Preliminary Stark effect experiments have been performed, yielding $\mu a=1.2(3)$, $\mu b=1.82(1)$, and $\mu c=0.7(4)D$. The rotational constants of the argon complex are fit best by a model that has the Ar atom situated on the same side of the ring as the hydroxyl group.