Highly Chemoselective Baylis−Hillman and Aldol Reactions of 2<i>H</i>-Thiopyran-4(3<i>H</i>)-one Using Tertiary Amine Catalysts in Aqueous Media
作者:Bagher Eftekhari-Sis、Ali Akbari、Klaus Harms
DOI:10.1021/ol101883g
日期:2010.10.15
Baylis−Hillman (BH) reaction of 2H-thiopyran-4(3H)-one is investigated, and surprisingly, the reaction of 2H-thiopyran-4(3H)-one with aldehydes in the presence of different tertiary amines shows excellent chemo- and regioselectivity in water. At room temperature, DBU affords BH adducts, but with DABCO, aldol products were obtained. In the case of DABCO, Et3N, or DMAP, domino aldol−rearrangement reactions occurred
对于第一次,的Baylis-希尔曼(BH)的2个反应ħ -噻喃-4-(3 ħ) -酮进行了研究,并且令人惊讶地,反应2 ħ -噻喃-4-(3 ħ) -酮与醛在不同叔胺的存在在水中显示出优异的化学和区域选择性。在室温下,DBU提供BH加合物,但使用DABCO可获得醛醇产物。在DABCO,Et 3 N或DMAP的情况下,多米诺羟醛重排反应在45-50°C发生。