118385-22-1Relevant articles and documents
Syntheses and Reactions of 9-Substituted 10-Phenylthioxanthenium Salts: Negative Evidence for Thia-anthracene Oligomerisation
Hori, Mikio,Kataoka, Tadashi,Shimizu, Hiroshi,Ikemori, Megumi,Aoyama, Yasuko
, p. 1209 - 1218 (2007/10/02)
Various 9-aryl-10-phenylthioxanthenium salts have been prepared and their stereochemistry determined by (1)H n.m.r. spectroscopy.Reactions of the 10-phenylthioxanthenium salts or 10-phenyl-10-thia-anthracenes with aryl-lithiums have been studied in order to investigate whether or not 10-thia-antracenes cause oligomerisation.The 10-phenylthioxanthenium salts reacted with aryl-lithiums to give 9-phenylthioxanthenes in good yields.However, 10-phenylthioxanthenium salt (19) when treated with phenyl-lithium at -15 to -20 deg C gave 9-phenylthioxanthenol (38) (17percent) together with 9-phenylthioxanthene (13) because of the lability of 10-phenyl-10-thia-anthracene to air. 10-Phenyl-9-(p-tolyl)-10-thia-anthracene (50) generated in situ from the sulphonium salt (22) and lithium diisopropylamide failed to react with p-tolyl-lithium.An isolable ylide, 9-benzoyl-10-phenyl-10-thia-anthracene (52) was treated with p-tolyl-lithium at 0 deg C to give 9-benzoylthioxanthene (4) (82percent).In contrast, 9,9,10-triphenylthioxanthenium salt (24) on treatment with phenyl-lithium gave a ring-opened product (40), a ring-contracted product (41), diphenylsulphide (42), and 9,9-diphenylthioxanthene (12).These results indicate that the 10-phenyl-thia-anthracenes or the ?-sulphuranes of thioxanthenes do not cause oligomerisation.
