Chemical transformations of solvent-derived ozonolysis products: Acid-catalysed reactions of α-alkoxy α′-hydroperoxy isochromans with aldehydes

a-(2,2,2-Trifluoroethoxy) a'-hydroperoxy cyclic ethers 6, derived from the ozonolysis of 1-substituted indenes in 2,2,2-trifluoroethanol, undergo acid-catalysed cyclocondensations with aliphatic aldehydes to yield 1,2,4,6-tetroxepanes 8. With formaldehyde, hydroperoxides 6 afford the structurally novel 1,2,4,6,8-pentoxonane derivatives 9 in addition to 1,2,4,6-tetroxepanes. In contrast, the analogous acid-catalysed cyclocondensations involving the isomeric hydroperoxides 7 result in extensive degradation, though acidolysis of hydroperoxides 7 gives rise to the symmetrical 1,2-dialkyl peroxides 16.