Pcb. Page et al., LEWIS-ACID MEDIATED ADDITION OF 2-ACYL-1,3-DITHIANES TO ALPHA,BETA-UNSATURATED KETONES - SYNTHESIS OF CYCLOHEXENEDIONE MONO-DITHIOACETALS, Tetrahedron, 49(45), 1993, pp. 10369-10386
2-Acyl-1,3-dithianes undergo Lewis acid-mediated conjugate addition to
alpha,beta-unsaturated ketones to provide 1,5-diketones which suffer
base-catalyzed intramolecular aldol reaction to produce monodithioacet
als of cyclohex-2-en-1,4-diones and cyclohex-3-en-1,2 diones.