Ru及びIr錯体上でのヘテロ元素置換内部アルキンのビニリデン転位

概要

The vinylidene rearrangement at a transition metal center, in which a coordinating alkyne is transformed into the corresponding vinylidene ligand, is among the most important transition-metal-promoted reactions of alkynes and has been applied widely to organic synthesis.1 Although there have been many reports on this type of rearrangement using terminal- and siliconsubstituted alkynes,2 similar transformation of carbondisubstituted3 and group 15/16 element-substituted4 internal alkynes still remains to be explored. Since the discovery of vinylidene rearrangement of simple dialkyl- and diarylalkynes at a ruthenium center,5 this laboratory has been engaged in expanding the scope of this transformation from both viewpoints of the group migrating and the reaction site. 6 In fact, vinylidene rearrangement of phosphoryl-, sulfonyl-, and arylthiosubstituted internal alkynes has recently been achieved at a cationic ruthenium center.7 In this work, the author has investigated this rearrangement of N-substituted internal alkynes at ruthenium and iridium complexes and S-substituted internal alkynes at an iridium complex.