1,1 carboboration delivers both the carbon-carbon bond and the carbon-boron bond to the same carbon in the substrate. It requires a 1,2-migration of a substituent from one carbon to the other in the double bond. The Wrackmeyer reaction is typically credited as being the pioneering example of 1,1 carboboration and utilizes a metal migrating group to help facilitate the transformation. However, there are several modern examples of carboboration with a variety of migrating groups.
The Wrackmeyer reaction involves 1,1 carboboration of a 1-alkynylmetal compound to yield alkenylborane compounds. [M] can be silicon, germanium, tin, or lead compounds with various substituents or ligands. [M] and BR are typically cis to one another in the Wrackmeyer reaction, with some exceptions.