Dehydrative Reduction: A Highly Diastereoselective Synthesis of syn-Bisaryl(or Heteroaryl) Dihydrobenzoxathiins and Benzodioxane
摘要:
[GRAPHICS]TFA/Et3SIH-mediated cyclization of thioketones 5 derived from the reaction of functionalized thiophenols (catechols) with bromo ketones gave syn 2,3-bisaryl(or heteroaryl) dihydrobenzoxathiins and benzodioxane 1 with total diastereoselectivity (>99:1), in excellent yields.