Ozone in Polar (Acetonitrile) and Nonpolar (Carbon Tetrachloride) Organic Liquids: Optical Absorption, Solubility, and Stability

Abstract

The optical characteristics, solubility, and decomposition kinetics of ozone in polar (acetonitrile, CH 3 CN) and nonpolar (carbon tetrachloride, CCl 4 ) liquids in the temperature range 233.15-295.15 K were studied. The rate constants of the O 3 decomposition at 295.15 K in CH 3 CN and CCl 4 are 3.3 × 10 À 5 and 5.0 × 10 À 5 s À 1 , respectively. At low temperatures, ozone solu-tions are practically stable. The solubility coefficients at 295.15 K are 2.6 in CH 3 CN and 2.9 in CCl 4 ; at 233.15 K, they increase to approximately 7.0. Thus, these two liquids have a set of properties making them optimum for studying the ozonolysis in polar and nonpolar media.

Effect of Solvent on the Rate of Ozonolysis: Development of a Homogeneous Flow Ozonolysis Protocol

“…While the O 3 concentration in DCM at −80 °C was much lower than other solvents, we saw this as an opportunity to showcase the reagent control that continuous flow reactors can achieve over some batch systems with dilute O 3 solutions. Solutions of O 3 in DCM were prepared on mmol scale and immediately fed into the continuous flow reactor at controlled flow rates. , A quick screen of O 3 equivalence in the homogeneous flow reactor showed low conversion at −78 °C with 3.0 equiv of O 3 giving 62% conversion of 5 (Table , entry 3). To increase the conversion of 5 into 6 under mild conditions, we warmed the reactor to 0 °C.…”

“…Solutions of O 3 in DCM were prepared on mmol scale and immediately fed into the continuous flow reactor at controlled flow rates. 34,35 A quick screen of O 3 equivalence in the homogeneous flow reactor showed low conversion at −78 °C with 3.0 equiv of O 3 giving 62% conversion of 5 (Table 3, entry 3). To increase the conversion of 5 into 6 under mild conditions, we warmed the reactor to 0 °C.…”