Substitution and Catalytic Chemistry of Gyroscope‐Like Complexes Derived from Cl–Rh–CO Rotators and Triply trans Spanning Di(trialkylphosphine) Ligands. Issue 32 (22nd October 2015)

• Record Type: Journal Article
• Authors: Estrada, Alexander L.; Jia, Tiezheng; Bhuvanesh, Nattamai; Blümel, Janet; Gladysz, John A.
• Is Part Of: European journal of inorganic chemistry. Issue 32(2015)
• Page Start: 5318
• Page End: 5321
• Publication Date: 2015-10-22
• Subjects: Rhodium -- Substitution reactions -- Borohydride complexes -- Cage compounds -- Hydroformylation -- Molecular rotors; Chemistry, Inorganic -- Periodicals; Organometallic chemistry -- Periodicals; Bioinorganic chemistry -- Periodicals; Solid state chemistry -- Periodicals; 546
• DOI: 10.1002/ejic.201500953
• Languages: English
• ISSNs: 1434-1948

Abstract

Abstract: Reactions of trans ‐[Rh(CO)(Cl){P{(CH2 )14 }3 P 2 (Rh–P 2 ) }] (1 ) with ZnPh2, MeLi, or NaBH4 give the chloride‐substitution products trans ‐[Rh(CO)(Ph){P{(CH2 )14 }3 P 2 (Rh–P 2 ) }] (3, 89 %), trans ‐[Rh(CO)(Me){P{(CH2 )14 }3 P 2 (Rh–P 2 ) }] (94 %, 92 % purity), and trans ‐[Rh(CO)(H2 BH2 ){P{(CH2 )14 }3 P 2 (Rh–P 2 ) }] (5, 99 %). The crystal structures of3, 5, and the corresponding (fortuitously obtained) bromide complex are determined, and the ability of the X–Rh–CO moieties to rotate is interpreted in terms of their effective radii and the void space within the dibridgehead diphosphine cage. Reaction of1 and excess PMe3 gives the diphosphine substitution product trans ‐[Rh(CO)(Cl)(PMe3 )2 ] (89 %) and the dibridgehead diphosphine P[(CH2 )14 ]3 P (58 %). Complex5 serves as a catalyst precursor for the hydroformylation of 1‐octene (neat or THF, 60 °C, 75 psig 1:1 CO/H2 ). The locus of catalysis with respect to the diphosphine cage is discussed. Abstract : The gyroscope‐like complex1 reacts with nucleophiles to give either chloride‐ligand‐substitution products, which leave the cage structure intact, or diphosphine‐ligand‐substitution products, which expel the rhodium. The formation of rhodium–carbon or rhodium–hydrogen linkages can facilitate entry into catalytic cycles, and the hydroformylation of 1‐octene can be effected.