ORGANIC SYNTHESIS USING HALOBORATION REACTION. I. A SIMPLE AND SELECTIVE SYNTHESIS OF 2-BROMO- AND 2-IODO-1-ALKENES

Article abstract of DOI:10.1016/S0040-4039(00)81511-7

B-bromo- or B-iodo-9-borabicyclo<3.3.1>nonane reacts readily with 1-alkynes.Such haloboration reactions proceed through the Markovnikov addition of the X-B moiety to C<*>C bonds and cis fashion.The bromoboration reaction occours chemoselectively at terminal C<*>C bonds but not at internal C<*>C, terminal and internal C=C bonds.The protonolysis of haloboration products with acetic acid gives corresponding 2-bromo- or 2-iodo-1-alkenes in excellent yields.