Laser-induced decompositions of 3,5-dimethyl-1,2,4-trioxolane (secondary butene-2-ozonide) in the gas phase

Abstract

UV (ArF and N₂) laser photolysis and IR laser photosensitized (SF₆) decomposition of gaseous secondary butene-2-ozonide (SBOZ) are shown to follow different reaction courses. ArF laser (193 nm) photolysis of SBOZ affords CO₂, CH₃OH, CH₃CHO, CH₄, HCOOH, CH₂CO and C₁–C₄ hydrocarbons, while N₂ laser (337 nm) photolysis of SBOZ is a much slower process than SBOZ oligomerization occurring on the reactor walls. The multiple of the ArF laser induced photolytic products is in line with a complex reaction scheme involving initial O–O and 2,3 C–O bond splits of 1,2,4-trioxolane ring. Continuous-wave CO₂ laser photosensitized SBOZ decomposition affords CH₃CHO and CH₃COOH together with 1-hydroxylethyl acetate and 1-methoxyethyl formate, the products of rearrangement observed earlier in a pulsed CO₂ laser SF₆ photosensitized decomposition reported by us in a previous paper.