A Novel Dimer of α -Tocopherol

Abstract

Decomposition of the complex 4 , formed between the α -tocopherol ortho -quinone methide ( 2 ) and NMMO, by fast heating from − 78 ∘ C to 70 ∘ C in inert solvents produces a novel α -tocopherol dimer with 6 H , 12 H -dibenzo[b,f][1,5]dioxocine structure ( 5 ) which—in contrast to the well-known spiro-dimer of α -tocopherol ( 3 )—is symmetrical. This is the first example of a direct reaction of the highly transient zwitterionic, aromatic precursor 2a in the formation of the ortho -quinone methide 2 .