Development of New and Efficient Organic Transformations Catalyzed by Molybdenum

我们开发了一种基于钼的新型催化剂，该催化剂是通过六羰基钼与炔丙基溴反应原位制备的。该催化剂促进具有两个末端炔烃的二炔与炔丙基溴的[2 2 2]-共环化以产生取代的苄基溴衍生物。当二炔同时具有末端炔和内部炔时，与炔丙基溴反应生成环化溴二烯衍生物，且不掺入炔丙基溴的炔部分。此外，丙二烯基乙酸甲酯与炔丙基溴在正炔丙基钼催化下反应，得到2-溴-1,3-丁二烯衍生物。还研究了这些反应的范围和局限性。由于没有其他过渡金属络合物介导这些反应，我们的发现应该是钼固有的有机转化。

We developed a new catalyst based on molybdenum, which was made in situ by reaction of molybdenum hexacarbonyl with Propargyl bromide. The catalyst promoted [2+2+2]-cocyclization of diynes having both terminal alkynes with propargyl bromide to produce substituted benzyl bromide derivatives. When diynes had both terminal and internal alkynes, the reaction with propargyl bromide produced cyclized bromodiene derivative without incorporation of alkyne part of propargyl bromide. In addition, reaction of allenylmethyl acetate with propargyl bromide catalyzed by n-propargylmolubdenum gave 2-bromo-1,3-butadiene derivatives. The scope and limitation of these reactions was also investigated. Since no other transition metal complexes mediated these reactions, our findings should be inherent organic transformations of molybdenum.