Abstract
Reaction of 2,2"-dithiodibenzaldehyde 1 with activated alkenes 2a -g in the presence of 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) affords, in one step, 3-substituted 2H -1-benzopyrans 6a -g in yields of up to 67%.
Key words
heterocycles - thiochromenes - 2H -1-benzothiopyrans - Baylis-Hillman methodology
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