Cobalt induced tandem C-H activation/decarbonylation of various aromatic aldehydes and related benzylic alcohols forming mononuclear aryl monocarbonyl complexes.
Reactions between Co(CH(3))(PMe(3))(4) and various ortho-substituted aromatic aldehydes (Ar(R(1),R(2))CHO) and related benzylic alcohols (Ar(R(1),R(2))CH(2)OH) proceed with high selectivity to give the mono carbonyl complexes Aryl(R(1),R(2))(PMe(3))(3)Co(CO): R(1) = H, R(2) = CH(3) (1), R(1)= H, R(2) = ethyl (2), R(1) = CH(3), R(2) = CH(3) (3), R(1) = H, R(2) = NH(2) (4), R(1) = F, R(2) = F (5), R(1) = H, R(2) = CF(3) (6), and R(1) = H, R(2) = benzo (7). This tandem C-H bond activation/decarbonylation reaction provides easy and rapid access under mild conditions (-70 degrees C) to the first isolated trimethylphosphine stabilized aryl-monocarbonyl complexes of cobalt. X-ray diffraction studies were performed on ortho-amino substituted complex 4, ortho-trifluormethyl 6, and naphthyl derivative 7.
Beck
Robert
R
Eduard-Zintl-Institut für Anorganische and Physikalische Chemie, Technische Universität Darmstadt, Petersenstrasse 18, D-64287 Darmstadt, Germany. metallacycle@gmail.com
Flörke
Ulrich
U
Klein
Hans-Friedrich
HF