K. Tanaka et al., SYNTHESIS, STRUCTURE AND PROPERTIES OF [7]HETEROHELICENES POSSESSING PHENOLIC HYDROXY FUNCTIONS, Chemistry Letters, (6), 1997, pp. 501-502
Photocyclization of oxy)-phenylvinylene]benzo[1,2-b:4,3-b']dithiophene
affords three regioisomers of the bis(silyloxy)[7]thiaheterohelicenes
together with the unexpected 4-phenyl-substituted [7]thiaheterohelice
ne. Cleavage of the silyl ethers gave the helical quinone, which inclu
des ethanol as guest molecules to form a 1:1 inclusion complex.