α-Bromoacetate as a Mild and Safe Brominating Agent in the Light-Driven Vicinal Dibromination of Unactivated Alkenes and Alkynes.

Light-induced vicinal dibromination of unactivated alkenes and alkynes has been demonstrated by using methyl α-bromoacetate as a mild brominating agent. A near-visible light (370 nm) light-emitting diode (LED) mediates this simple dibromination reaction under mild conditions with the inexpensive and nontoxic α-bromoacetate. The reaction proceeds well with both terminal and internal alkenes and alkynes and those contained in N/O-heterocycles, indicating its versatility in synthesizing dibrominated organic compounds.