Ruthenium cluster chemistry: Monodentate bis(diphenylphosphino)acetylene-ligated cluster modules in chain and dendrimer formation

A Straightforward Synthesis of 5‐Methylaaptamine from Eugenol, Employing a 6π‐Electrocyclization Reaction of a 1‐Azatriene

“…The longest Ru–Ru bond length [Ru1–Ru3 = 2.8930(6) Å] is cis to the monodentate AsPh 3 ligands, while the bridged Ru–Ru distance [Ru1–Ru2 = 2.8461(7) Å] is slightly shorter than the unbridged Ru2–Ru3 bond [2.8495(7) Å]. Similar observations were also made in Ru 3 (CO) 9 (dppm)AsR 3 ,12 Ru 3 (CO) 9 (dppm)P R 3 [ R = Ph, Cy, i Pr, (Et),14 Ru 3 (CO) 9 (dppm)(dppa),18 and Ru 3 (CO) 9 (dppm)P(C 4 H 3 S) 3 19]. Koutsantonis and co‐workers remarked that the longest Ru–Ru bond cis to monodentate P ligands is correlated with the size of the ligand 14.…”

Reactivity of the triruthenium ortho-metalated cluster [Ru3(CO)9{μ3-η1,κ1,κ2-PhP(C6H4)CH2PPh}] with tri(2-thienyl)phosphine and tri(2-furyl)phosphine: Formation of 1,3-diphenyl-2,3-dihydro-1H-1,3-benzodiphosphine complexes via phosphorus–carbon bond formation

“…The PTh 3 ligand occupies an equatorial coordination site on the remote metal, Ru(1), while the dpbm ligand bridges the Ru(2)-Ru(3) edge and also lies in the equatorial plane. These features are fully consistent with the observed structures of [Ru 3 -(CO) 9 (PR 3 )(l-dppm)][12,[15][16]. The Ru-P bond distances involving the dpbm ligand [Ru(2)-P(2) 2.3197(8) and Ru(3)-P(3) 2.3131(8) Å] are very similar to those observed in both polymorphs of [Ru 3 (CO) 10 (l-dpbm)] [av.…”

“…13.6048 (10) 19.8514 (17) 12.0494(11) c (Å) 16.2662 (12) 18.6841 (16) 15.0970 (14) a ( inequivalent methylene protons of the backbone. For 3 these appear at d 4.24 and 3.57 and for 4 at d 4.27 and 3.51.…”

Facile Single or Double C−H Bond Activation on a Cp* Ligand Promoted by the Presence of Alkynylphosphine Ligands

“…On the other hand, alkynylphosphines have been shown to be a very useful type of ligand with excellent promise in coordination chemistry, mainly due to their ability to coordinate via the phosphorus atom and/or the CC moiety, thus favoring the formation of a rich variety of homo- and heteropolynuclear species. – Furthermore, they present a varied and rich chemistry related to several processes, among which are (i) the phosphorus−carbon bond cleavage to generate phosphido and alkynyl fragments via interaction with metal carbonyl clusters, ,− (ii) their possible engagement in characteristic insertion reactions of the triple bonds ,− or their activation with electrophilic or nucleophilic substrates, − and also (iii) intermolecular coupling of the alkynyl moieties leading to the association of two coordinated alkynylphosphines. ,,− The last reactions are of particular interest, owing to the fact that they are employed in the synthesis of macrocyclic systems from bis(diphenylphosphino) complexes with high atom efficiency , and in the study of Bergman-cyclization processes of bis(phosphino)enediynes upon complexation to metal ions. ,, Our research group has obtained very interesting results in the study of these coupling reactions on platinum and palladium precursors containing at least two alkynylphosphines, having reported the formation of novel coordinated diphosphinonaphthalene or 1,2-diarylalkenyl-1,2-diphosphine ligands, activated by complexation of a “ cis -Pt(C 6 F 5 ) 2 ” fragment, , under thermal or photochemical conditions …”

“…On the other hand, alkynylphosphines have been shown to be a very useful type of ligand with excellent promise in coordination chemistry, 29 eropolynuclear species. [29][30][31][32][33][34][35][36][37][38][39][40][41][42][43][44][45][46][47] Furthermore, they present a varied and rich chemistry related to several processes, among which are (i) the phosphorus-carbon bond cleavage to generate phosphido and alkynyl fragments via interaction with metal carbonyl clusters, 29, [48][49][50] (ii) their possible engagement in characteristic insertion reactions of the triple bonds 35,[51][52][53][54][55] or their activation with electrophilic or nucleophilic substrates, [56][57][58] and also (iii) intermolecular coupling of the alkynyl moieties leading to the association of two coordinated alkynylphosphines. 31,52,[59][60][61][62][63][64][65][66] The last reactions are of particular interest, owing to the fact that they are employed in the synthesis of macrocyclic systems from bis(diphenylphosphino) complexes with high atom efficiency 61,62 and in the study of Bergmancyclization processes of b...…”