Synthesis and Reactivity of Organometallic Intermediates Relevant to Cobalt-Catalyzed Hydroformylation.

Autor: MacNeil CS; Department of Chemistry, Princeton University, Frick Laboratory 292, Princeton, NJ, 08544, USA., Mendelsohn LN; Department of Chemistry, Princeton University, Frick Laboratory 292, Princeton, NJ, 08544, USA., Zhong H; Department of Chemistry, Princeton University, Frick Laboratory 292, Princeton, NJ, 08544, USA., Pabst TP; Department of Chemistry, Princeton University, Frick Laboratory 292, Princeton, NJ, 08544, USA., Chirik PJ; Department of Chemistry, Princeton University, Frick Laboratory 292, Princeton, NJ, 08544, USA.
Jazyk: angličtina
Zdroj: Angewandte Chemie (International ed. in English) [Angew Chem Int Ed Engl] 2020 Jun 02; Vol. 59 (23), pp. 8912-8916. Date of Electronic Publication: 2020 Mar 30.
DOI: 10.1002/anie.202001677
Abstrakt: Intermediates relevant to cobalt-catalyzed alkene hydroformylation have been isolated and evaluated in fundamental organometallic transformations relevant to aldehyde formation. The 18-electron (R,R)-( iPr DuPhos)Co(CO) 2 H has been structurally characterized, and it promotes exclusive hydrogenation of styrene in the presence of 50 bar of H 2 /CO gas (1:1) at 100 °C. Deuterium-labeling studies established reversible 2,1-insertion of styrene into the Co-D bond of (R,R)-( iPr DuPhos)Co(CO) 2 D. Whereas rapid β-hydrogen elimination from cobalt alkyls occurred under an N 2 atmosphere, alkylation of (R,R)-( iPr DuPhos)Co(CO) 2 Cl in the presence of CO enabled the interception of (R,R)-( iPr DuPhos)Co(CO) 2 C(O)CH 2 CH 2 Ph, which upon hydrogenolysis under 4 atm H 2 produced the corresponding aldehyde and cobalt hydride, demonstrating the feasibility of elementary steps in hydroformylation. Both the hydride and chloride derivatives, (X=H - , Cl - ), underwent exchange with free 13 CO. Under reduced pressure, (R,R)-( iPr DuPhos)Co(CO) 2 Cl underwent CO dissociation to form (R,R)-( iPr DuPhos)Co(CO)Cl.
(© 2020 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)
Databáze: MEDLINE
Externí odkaz: