REACTIONS OF 3,5-DIARYL-1,2-DITHIOLIUM SALTS AND 3,5-DIARYL-1,2,4-DITHIAZOLIUM SALTS WITH METAL CYCLOPENTADIENIDES

Reaction of the 3,5-diaryl-1,2-dithiolium salts 2 with the metal cyclo pentadienides 4 and 9 leads to the formation of the tricyclic compound s 6 and 10 via a ring-opened intermediate, which undergoes an intramol ecular Diels-Alder cyclization. Compounds 6 and 10 rearrange by treatm ent with boron trifluoride-diethyl ether to the isomeric compounds 7 a nd 11. The structures 6f and 7f were confirmed by X-ray analysis. Cond ensation of the 3,5-diaryl-1,2,4-dithiazolium salts 3 with the metal c yclopentadienides 4 affords the tricyclic compounds 12, which do not r earrange by Lewis acid catalysis.