Double C-H activation during functionalization of phenyl(methyl)ketene on iridium(I) using alkynes. synthesis of 1,4-dien-3-ones.
Under the influence of an Ir(I) metal fragment, the methyl group of phenyl(methyl)ketene undergoes two C-H activations in reacting with internal alkynes, giving metallacycles 3 in 86-94% yield. Treatment of 3 with CO liberates 1,4-dien-3-ones 5 in 81-93% yield, along with CO complex 4. A possible mechanism for the very selective double C-H activation-alkyne coupling is discussed.
Grotjahn
Douglas B
DB
Department of Chemistry, San Diego State University, 5500 Campanile Drive, San Diego, California 92182-1030, USA. grotjahn@chemistry.sdsu.edu
Hoerter
Justin M
JM
Hubbard
John L
JL