In Situ Generation of Silylzinc by Si-B Bond Activation Enabling Silylzincation and Silaboration of Terminal Alkynes.

A new protocol has been designed for the in situ generation of unstable Si-Zn species through the reaction of dialkylzinc, phosphine, and silylborane (Si-B). Successive reactions with various terminal alkynes using this protocol enabled highly controllable regio-/stereo-/chemoselective silylzincation and silaboration on demand without the need for a transition-metal catalyst.