Abstract
The closely related title compounds, 1-(dinaphtho[2,1-d:1 ',2 '-f][1,3]dithiepin-4yl)-2,2-dimethylpropan-1-ol, C26H24OS2, 1 and 2-(dinaphtho[2,1-d:1 ',2 '-f][1,3]dithiepin-4-yl)-3,3-dimethylbutan-2-ol, C27H26OS2, 2, both comprise an atropisomeric binaphthyl dithioacetal unit substituted at the methylene carbon atom with a chiral neopentyl alcohol grouping. The overall stereochemistry of the racemate in each case is defined alpha s alpha S,R and alpha R,S. In 1, the hydroxyl group generates inversion dimers via pairwise intermolecular O-(HS)-S-. . . hydrogen bonds whereas in 2, the O-(HS)-S-. . . link is intramolecular. Weak C-H-... pi interactions link the molecules into extended arrays in both structures.