Gold-catalyzed addition of sulfonic acids to alkynes to form vinyl sulfonates

摘要

In the presence of a catalytic amount of (Ph_3R)AuNO_3 and phthalimide, the addition of toluenesulfonic acid or methanesulfonic acid to alkynes has been shown to proceed and gives vinyl tosylates and vinyl mesylates in good yields and regioselectivity.rnDuring the past ten years, several research groups have developed gold-catalyzed homogeneous catalytic reactions. A variety of organic transformations have been shown to be mediated by gold(ⅰ) or gold(ⅲ) complexes in solution. In addition to its ability to activate alkynes and related substrates, the catalysis of nucleophilic addition by gold complexes for the formation of carbon-carbon and carbon-heteroatom bonds has been one of the most investigated reactions in modern organometallic catalysis. Various nucleophilic reagents, such as water, alcohols, amines, acetic acid etc., have been used in the intermolecular addition to alkynes. As part of our ongoing studies on metal-catalyzed atom-economical reactions, we have been interested in the use of gold for simple and highly efficient transformations. On the other hand, vinyl sulfonates are important building blocks in organic synthesis, especially as electrophiles for cross-coupling chemistry.