A Bimetallic, Coordinated‐Ketene Complex Formed from a Bimetallic Lithium–Carbon Spirocycle by Lithium‐Mediated Insertion of CO into a Rhodium–Carbon Bond

Abstract

Metals helping metals: The bimetallic spirocyclic bridged‐carbene complex 1 reacts almost quantitatively with CO by formal “insertion” into the RhC(Li) bond to form the dimeric complex 2, the first example of a μ2,η2‐(O,C) lithium–rhodium ketene complex (see scheme). Complex 2 reacts with water to transform the ketene ligand into a methine group by CO elimination.

Heterobimetallic Pd–K carbene complexes via one-electron reductions of palladium radical carbenes

“…Heterobimetallic carbene complexes 73 , 74 containing K–C carbene –M units, in which the carbene is not stabilized by adjacent heteroatoms, are rare; 23 , 75 to the best of our knowledge, complexes 4 and 5 represent the only known characterized heterobimetallic carbene species possessing such binding motifs. The successful synthesis of amide substituted carbene complexes 4 and 5 from the radical precursor 1 prompted us to investigate other nucleophiles, especially those featuring an alkyl group.…”

Geminal dianions stabilized by phosphonium substituents

“…Apart from metal exchange reactions discussed in Section 2.2, these methandiides are generally used as precursors for a variety of metal carbene complexes and the metathesis reactions with several metal salts have been described [16]. Of interest is the reaction of Li 2 C[PPh 2 N(SiMe 3 )] 2 with (COD)RhCl and subsequent conversion with CO (Scheme 8) [43]. More advanced reactivity studies have been done on the methandiide Li 2 C(Ph 2 P S) 2 (25, Scheme 9) [25, 44,45].…”

Coordination Behavior of the S–C–S Monoanion and O–C–O and S–C–S Dianions toward CoII

“…Indeed, reactions of 1 -with either Rh I or Ir I precursors leads to a complex of type B (Scheme 2), [9] and reaction of 1 2-with one equivalent of Rh I precursor resulted in the formation of a mixed Rh-Li complex. This complex could then be reacted with another equivalent of metal precursor to generate bimetallic complexes, in which the dianion acts as a bridging moiety, reminiscent of structure E. [10] We have recently reported that the reaction of 2 -with one equivalent of Ir I precursor led to the formation of an Ir III complex resulting from the CH insertion in one phenyl substituent of the ligand. [11] Finally, the reaction of two different ligands of type 1 -(R = C 6 H 2 Me 3 and C 6 H 3 iPr 2 ) with CoCl 2 is reported to form a complex of the type [(1)CoCl], yet their structures (B or C) are not known.…”