28793-21-7Relevant articles and documents
OZONOLYSIS OF THE TETRAMETHOXYETHENE
Kopecky, Karl R.,Molina, Jose,Rico, Rodrigo
, p. 2234 - 2243 (2007/10/02)
Ozonolysis of tetramethoxyethene 1 produces 20 40 percent of dimethyl carbonate3, 35-60 percent of methyl trimethoxyacetate 7, and 20-35 percent of the dioxetane 8 of 1.Yields vary with initial concentration of 1, temperature, and solvent.Singlet oxygen is produced, which reacts with 1 to from 8 and can be trapped with 2,5-dimethylfuran.No evidence for the formation of the molozonide of 1 was obtained.Up to 2.5 moles of 1 are consumed per mole of ozone.Ozonolysis of a mixture of 1 and 2,3-dimethyl-2-butene 12 gave the epoxide of 12 and three times the expected amount of the allylic hydroperoxide of 12.A competing radical chain oxidation is proposed to account for these products and the stoichiometry of the ozonolysis.The initialreaction in the ozonolysis of 1 is proposed to be en electron transfer reaction that is calculated to be exothermic by >35 kcal/mol.The resulting radical ions initiate the radical chain oxidation and combine to form the oxygenated epoxide 9 of 1.Loss of singlet oxygen from 9 forms the epoxide 10, which rearranges to 7.At -95 deg C the zwitterion from 10 is trapped by CD3OD to produce a mixture of 7 with one α OCD3 group and pentamethoxyethanol with one β OCD3 group from which a CH3OD group is lost at ca. -10 deg C to form more deuterated ester.
