ISOLATION OF OZONIDES FRONT GAS-PHASE OZONOLYSES OF TERPENES

Ozonolyses of (-)-beta-pinene (1) and of (+)-sabinene (6) in the gas p hase afforded the corresponding ozonides clo[3.1.1(1,5)]heptane[2-spir o-3]-1,2,4-trioxolane (2) and yclo[3.1.0(1,5)]hexane[2-spiro-3]-1,2,4- trioxolane (7), which were isolated as mixtures of two diastereomers e ach. Major products were the corresponding ketones 6,6-dimethyl-2-oxob icyclo[3.1.1(1,5)]heptane (3) and 5-isopropyl-2-oxobicyclo[3.1.0(1,5)] hexane (8). Additional products were the lactones 7,7-dimethyl-2-oxa-3 -oxobicyclo[4.1.1(1,6)]octane (4) and 7,7-dimethyl-3-oxa-2-oxobicyclo[ 4.1.1(1,6)]octane (5) derived from P-pinene (1) as well as 6-isapropyl -2-oxa-3-oxobicyclo[4.1.0(1,6)]heptane (9) and 6-isopropyl-3-oxa-2-oxo bicyclo[4.1.0(1,6)]heptane (10) derived from sabinene (6).