A Mild and General <i>trans</i>-Diboration\nof Both Terminal and Internal Propargyl Alcohols

A practical and efficient <i>trans</i>-diboration\nof\npropargyl alcohols was accomplished using sodium hydride (NaH) as\na base in <i>N</i>,<i>N</i>-dimethylformamide\nat room temperature. The mild reaction conditions demonstrate general\napplicability, facilitating the successful conversion of both terminal\nand internal propargyl alcohols with diverse structures and functional\ngroups into highly functionalized alkenediboronates [4-borylated 1,2-oxaborol-2(5<i>H</i>)-oles]. The resulting products, which incorporate two\nboron groups, can be selectively activated and subjected to stepwise\ntransformations, thereby providing an effective platform for synthesizing\na wide range of structurally diverse trisubstituted alkenes.