A New Approach to 1,2,4‐Trioxanes form Cyclic Allylic Hydroperoxides

Abstract

Abstract Summary The reaction of 4,5‐dimethyl‐4‐hydroperoxy‐1(4 H )‐nephthalenone ( 9 ) with acetaldehyde, pivalaldehyde, benzaldehyde, and p ‐chlorobenzaldehyde in CH 2 Cl 2 in the presence of Amberlyst ‐ 15 as catalyst gave the corresponding cis ‐3‐methyl, t ‐butyl, phenyl and p ‐chlorophenyl derivatives of 10,10b‐dimethylnaphtono[2,1‐ e ][1,2,4]trioxin‐6(5) H ‐one in 80‐95% yields. Acetone reacted similarly with 9 to give the 3,3′ ‐dimethyl derivative. Configurations of all trioxinones were assigned by comparison of their spectral properties with that of the p ‐chloro derivative whose structure was determined by X‐ray. 2,5‐Diphenyl‐2‐hydroperoxypyrrole was less efficient that 9 , but it condensed with acetaldehyde and pivaladehyde under the same conditions giving the cis ‐ 3‐methyl and cis ‐ 3‐( t ‐butyl) derivatives of 6,7a‐diphenyl‐4a, 7a‐dihydro‐3 H , 5 H ‐[1,2,4]trio‐xino[3,2‐ e ]pyrrole in 24 and 20% yield, respectively.