One-Pot Method for Regioselective Bromin­ation and Sequential Carbon–Carbon Bond-Forming Reactions of Allylic Alcohol Derivatives

One-Pot Method for Regioselective Bromin­ation and Sequential Carbon–Carbon Bond-Forming Reactions of Allylic Alcohol Derivatives

European Journal of Organic Chemistry Noriki Kutsumura, Yusuke Matsubara, Kentaro Niwa, Ai Ito and Takao Saito
DOI: 10.1002/ejoc.201300173

http://onlinelibrary.wiley.com/doi/10.1002/ejoc.201300173/abstract

Di- or trisubstituted olefins were synthesized in high yields with excellent regio- and cis–trans selectivities in one-pot reactions, including a regioselective DBU-promoted trans HBr elimination. This one-pot methodology could become a straightforward transformation of “straight” alkenes into “Y-shaped” alkenes.

An efficient one-pot method for the regioselective bromination of allylic alcohol derivatives (two-step reaction sequence) followed by Sonogashira, Negishi, or Suzuki–Miyaura coupling reactions in the same reaction vessel (three-step reaction sequence) has been developed. The key reaction in these one-pot systems is the regioselective DBU-promoted trans HBr elimination of vicinal dibromides bearing an adjacent O-functional group.