Synthesis and optical properties of chiral dinaphthofuran possessing two methyl groups in the bay region

8,8 '-dimethyl-1,1 '-bi-2-naphthol (7) was synthesized by oxidative dimerization of 8-methyl-2-naphthol (6). Camphorsulfonyl chloride was used as a chiral-resolving agent, followed by the synthesis of chiral dimethyl dinaphthofuran 3 by a dehydration reaction between two hydroxy groups without loss of optical purity. The racemization barrier and optical properties of the chiral compound 3 were scrutinized. Graphical Abstract 8,8'-dimethyl-1,1'-bi-2-naphthol (7) was synthesized by oxidative dimerization of 8-methyl-2-naphthol (6). Camphorsulfonyl chloride was used as a chiral resolving agent, followed by the synthesis of chiral dimethyl dinaphthofuran 3 by a dehydration reaction between two hydroxy groups without loss of optical purity. The racemization barrier and optical properties of the chiral compound 3 were scrutinized.