Visible‐Light‐Mediated C(sp
<sup>3</sup>
)–H Thiocarbonylation for Thiolactam Preparation with Potassium Sulfide
作者:Wei Tan、Cuihong Wang、Xuefeng Jiang
DOI:10.1002/cjoc.201900360
日期:2019.12
thiolactam preparation with potassium sulfide via visible‐light‐mediated C(sp3)–H thiocarbonylation, in which polysulfide dianions and radical anions generated from potassium sulfide were the key active species. A variety of thiolactams were straightforward established under mild conditions. Moreover, it was successfully applied to structural modification of tetrahydroberberine.
2-Alkyl-1-methylthioisoquinolinium salts were easily prepared from 2alkyl-1(2H)-isoquinolones via 2-alkyl-1(2H)-thioisoquinolones in two steps. Under mild conditions, the reaction of 2-alkyl-1-methylthioisoquinolinium salts with active methylene compounds in the presence of sodium hydride afforded 2-alkyl-1-(substituted methylene)isoquinolines in good yields. The cyclization of 2-benzylisoquinolines using acetic anhydride produced the pyrrolo[2,1-a]isoquinolines. Further, the reaction of 1-chloro-2-phenacylisoquinolinium salt with active methylene compounds afforded the pyrrolo[2,1-a]isoquinolines in one pot.