The microwave spectra and conformations of chloromethyl oxirane: cis and gauche-2 forms

The microwave spectra of two conformations of chloromethyl oxirane ($\text{CH}{}_2\text{OC}$HCH₂³⁵Cl, epichlorohydrin) is reported. In the gauche-2 form the chlorine is situated trans to the oxygen, in the cis form the chlorine is cis to the ring. The rotational constants in megahertz are gauche-2; A = 12 739.35, B = 2066.83, C = 1881.49, and cis; A = 8378.66, B = 2840.67, C = 2510.55.