Selective for oxygen isotopes IR multiphoton dissociation of isopropyl methyl ether

18O-selective IR-multiphoton dissociation of methylisopropyl ether is studied during the action of pulse CO2-laser. Yields of dissociation of each isotopic component (β18 and β16) and isotopic selectivity with respect to 18O (α = β18/β16) depending on frequency and energy density of laser radiation and also on own ether pressure are measured. On laser radiation frequency 1041.3 cm-1 yields and selectivity achieve β18 = 3.5%, α(18/16)=25 and β18=6.5%, α(18/16)=16 at energy density 3.0 and 3.5 γ/cm2 respectively. Main detected oxygencontaining products of dissociation of C3H7OCH3 are methanol and acetyl aldehyde, this points to the fact that decomposition of the molecule occurs at least by two ways. 15 refs., 3 figs