Carboberyllation: addition of organoberyllium species to alkenes and alkynes. A comparison with carboboration

Abstract

The potential for carbometallation reactions between organoberyllium and model alkenes and alkynes has been investigated in a computational study. Results indicate that barriers for carbometallation reactions between BeR₂ and alkynes are as low as 100 kJ mol⁻¹, and much lower than corresponding reactions with MgR₂. In contrast to carboboration reactions with BR₃, with organoberyllium 1,2-addition is favoured over 1,1-addition. It is concluded that carbometallation reactions with beryllium are likely feasible, and that the reaction between BePh₂ and alkynes provides the best opportunity for the first experimental observation of carboberyllation.