Facile Synthesis of Cyanide and Isocyanides from CO

The reaction of K[N(SiMe3)2] with 13CO proceeds in C6D6 or THF affording K13CN and O(SiMe3)2 under mild conditions as confirmed by crystallographic characterization of K(18‐crown‐6)CN. Similarly reaction of the alkali metal amides, M[N(SiR3)R′] (M=Li, K; R=Ph, Me; R′=alkyl, aryl) provides the corresponding 13C labeled isocyanide RN13C and MOSiR3, generally in high yields. In some instances, the use of the sterically bulky Ph3Si‐substituent is required to preclude 1,2‐silyl migration affording the silylcarbamoyl salt M[Me3SiC(O)NR′]. These reactions have been used to obtain 19 examples of 13C labelled isocyanides, and several examples of gram scale reactions are reported. The mechanism of the reactions is probed via reliable DFT calculations.