An original and facile method for the generation of β-naphtha-1-thioquinones using DAST and 2-naphthols has been developed. A series of dehydro-2-naphthol-1-sulphides or naphtha-oxathiane derivatives were synthesized by in situDiels–Alder cycloaddition reactions of β-naphtha-1-thioquinone with itself or various alkenes.
Phthalimidesulfenyl chloride 1 reacts with activated arenes 2a-g, to give monosubstituted derivatives 3a-g. Hydroxysulfenyl compounds 3a-d have been used as suitable source of alpha-oxothiones (ortho-thioquinones) 4a-d, which act as heterodienes in 4+2 cycloaddition reactions.