[Ru₃CO₆(η⁵:η¹‐C₅H₄)₃]: The First Six Membered Ru₃C₃ Ring Formed by Insertion of C₅H₄ Units into Metal–Metal Bonds of [Ru₃(CO)₁₂]

Abstract

A cyclic ruthenium trimer without metal‐metal bonding, the highly symmetrical trinuclear complex 1 is formed under mild conditions by the reaction of [Ru3(CO)12] and diazocyclopentadiene. Insertion of cyclopentadienyl units into RuRu bonds also leads to the formation of [Ru3(CO)10(C5H4)] and the dimer [Ru2(CO)4(C5H4)2].

Synthesis and Molecular Structure of Two Six-Membered Ru3C3 Rings Existing in Boat- and Chairlike Configurations Formed by Insertion of C9H6 Units into Metal−Metal Bonds of [Ru3(CO)12]

“…Isomers 3 and 4 are structurally analogous to the cyclopentadienyl cyclotrimer recently reported by us and ), including a significant shortening of the C(6)−C(7) and C(8)−C(9) distances.…”

“…In 3 the ring has a chair conformation (Ru and C atoms are at 0.75 and 0.65 Å from the plane of the chair), dictated by the C 3 molecular point symmetry. In 4 it has a boat conformation (Ru(1) and C(1c) are 0.87 and 0.34 Å from the mean plane through Ru(2), Ru(3), C(1a), and C(1b)) and, therefore, is similar to (but more asymmetrical than) that found in the Cp analogue . The calculation of the puckering coordinates ( q 2 , q 3 , φ 2 ; Table ) provides a more quantitative description of the Ru 3 C 3 rings.…”

“…Compound 1 was obtained in very low yield and was characterized only by its IR spectrum, being identical with that of the Cp analogue [Ru 3 (CO) 10 (C 5 H 4 )], obtained from the reaction between [Ru 3 (CO) 12 ] and diazocyclopentadiene, whose X-ray structure was determined . We postulate that, in the presence of diazoindene 1 readily converts into 2 and into the cyclotrimers 3 and 4 .…”

“…We recently reported a convenient stepwise synthetic route to a cyclic ruthenium trimer without metal−metal bonding . This route involves the use of diazocyclopentadiene as the precursor of cyclopentadienyl units to be inserted in metal−metal bonds of clusters.…”

Synthesis of [Re2(CO)8{μ-N2(C5H4)2}], Derived from the Reaction of [Re2(CO)8(MeCN)2] and Diazocyclopentadiene

“…In this complex, the organic ligand is σ-bonded to a [(η 5 -Cp)Mo(CO) 2 ] fragment and η 5 -bonded to a [(η 5 -Cp)Mo(CO)] unit. We recently reported the insertion of C 5 H 4 units from C 5 H 4 N 2 into metal−metal bonds of [Ru 3 (CO) 12 ] to afford complexes of the type [Ru 3 (CO) 10 (μ,η 1 :η 5 -C 5 H 4 )] and [Ru 3 (CO) 6 (μ,η 1 :η 5 -C 5 H 4 ) 3 ], thus establishing that C 5 H 4 N 2 is an effective precursor for the insertion of C 5 H 4 units into metal−metal bonds …”