First asymmetric synthesis of dihydrobenzo[c]phenanthrene-1,4-quinones with helical chirality

The first enantioselective synthesis of 12-tert-butyl substituted 7,8-dihydrobenzo[c]phenanthrene-1,4-quinones having helical chirality is achieved with good chemical and optical yields through a domino Diels–Alder reaction–sulfoxide elimination–oxidation process starting from enantiopure (S)-2-(p-tolylsulfinyl)-1,4-benzoquinone and 5-tert-butyl substituted 3-vinyl-1,2-dihydronaphthalenes as dienes.