Insertion of CO into a CH3-Pd Bond in a Heterodinuclear Complex (dpe)MePd-Co(CO)4. Preferential Insertion of Coordinated CO on a Cobalt Moiety

Abstract

A palladium-containing heterodinuclear complex (dpe)MePd-Co(CO)4 shows higher reactivity toward CO insertion than PdMeCl(dpe) and (dpe)MePt-Co(CO)4 to give an acetyl complex (dpe)AcPd-Co(CO)4. The insertion of CO ligand in Co(CO)4 is a kinetically favorable process.

Enhanced C−C Bond Formation of Heterodinuclear Methylplatinum−Molybdenum Complexes Having a Hemilabile Ligand with Dialkyl Acetylenedicarboxylate

“…A five-coordinate tbp structure formalism of the Pt center having a chelating P−N ligand, alkenyl carbon, Mo, and bridging carbonyl may also be possible, with the N(1) and C(19) atoms in apical positions, because the Pt(1), P(1), N(1), and C(19) atoms constitute an almost complete plane. An analogous structural feature was also observed for the independently prepared complex (dppe)(μ-CH 2 CCO 2 Me)Pt−MoCp(μ-CO)(CO), obtained by the reaction of (dppe)(Η)Pt−MoCp(CO) 3 with HC⋮CCO 2 Me 3f. It is interesting to note that the difference of oxidation states in 5 and 8 is reflected in their CO stretching bands, where the values for 5 are larger than those for 8 by ca.…”

“…The observed longer CC double bond is considered to be due to the effective π-back-donation from the Mo metal. Although the Pt−Mo distance 2.898(2) Å in 5 lies in a typical range of Pt−Mo single bonds which have been reported for dinuclear and cluster complexes such as (cod)PhPt−MoCp(CO) 3 (2.8320(12) Å),3b (Ph 2 C 2 H 4 NEt 2 -κ 2 N,P )MePt−MoCp(CO) 3 (2.8989(9) Å), Cp 2 Mo 2 Pt(μ-PPh 2 ) 2 (CO) 5 (2.860(2), 2.872(2) Å),10a and [(η 5 −C 5 H 4 Me)Mo(CO) 2 (μ-dppm)Pt(dppm)] + (2.912(4) Å),10b no actual Pt−Mo interaction is considered to be involved. The Mo moiety in 5 has adopted a three-legged piano-stool type geometry with two carbonyls and one π-bonded platinacyclobutenone ligand.…”

“…Heterodinuclear complexes have attracted intrinsic interest due to their possible cooperative effect of two different metal centers in catalytic and stoichiometric chemical reactions. − Introduction of an unsymmetrical chelating ligand into such dinuclear complexes is expected to provide a highly selective reaction environment, because preferential partial dissociation of the chelating ligand gives a specific vacant coordination site on a metal center . We recently reported the synthesis of hetrodinuclear organoplatinum complexes having a hemilabile P−N ligand (2-(diphenylphosphino)triethylamine), which show a facile and reversible Pt−N bond rupture causing high reactivity toward CO .…”

Multimetallic Complexes Featuring a Bridging N-heterocyclic Phosphido/Phosphenium Ligand: Synthesis, Structure, and Theoretical Investigation

“…It is also pertinent to comment on the relatively long Co–Pt interatomic distance of 2.8008(3) Å in 8 (sum of covalent radii of Co and Pt = 2.64 Å) . The Co–Pt distances in structurally characterized Co/Pt complexes range from (2.40 to 2.75). − The comparatively long Co–Pt distance in 8 indicates the absence of a covalent metal–metal interaction, although a weak donor/acceptor interaction is possible.…”

Diphosphine as an Overhead Bridge across a Heterometallic M−M‘ Bond. A Flexible Cluster System in (P−P)AuMn2(CO)7(μ-PPh2) that Accommodates All Common Diphosphines

“…A key interest in heterometallic systems stems from its unique ability to bring together entities of fundamentally different electronic properties . In proximity, they preserve their inherent characteristics, yet develop new traits that are dependent on the heterometallic system . This is a basic incentive that brought about the upheaval of heterometallic chemistry, especially in bimetallic catalysis, bifunctional polymers, soluble alloys, etc.…”