A Metallaanthracene and Derived Metallaanthraquinone

The influence of the nature of the transition-metal fragment on the Diels-Alder reactivity of metallaanthracenes has been explored computationally within the Density Functional Theory framework. It is found that the cycloaddition reactions with maleic anhydride become kinetically less favored for those processes involving metallaanthracenes compared with the analogous reaction involving the parent anthracene. The origins of this reduction in the Diels-Alder reactivity have been quantitatively analyzed in detail by using the activation strain model of reactivity in combination with the energy decomposition analysis method. In general, the transition-metal fragment makes the interaction energy between the reactants significantly lower, particularly at the transition state region, which is translated into a higher activation barrier. In addition, the influence of the aromaticity strength of the metallabenzene present in the considered metallaanthracenes on the barriers of the cycloaddition reactions has also been assessed.

“… Diels–Alder cycloaddition reaction between iridaanthracene 1 and maleic anhydride reported by Frogley and Wright (see ref. ).…”

Section: Introductionmentioning

confidence: 97%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Influence of the Transition‐Metal Fragment on the Reactivity of Metallaanthracenes

García-Rodeja

Fernández

2017

“…Reported metallacycles includem etallabenzenes, [1,2] metallabenzynes, [3,4] metallaannulenes, [5] and other metallacycles. Reported metallacycles includem etallabenzenes, [1,2] metallabenzynes, [3,4] metallaannulenes, [5] and other metallacycles.…”

Section: Introductionmentioning

confidence: 99%

Synthesis and Characterization of Photothermal Osmium Carbolong Complexes

Qin

Lin

et al. 2018

Metallacycles with chelating polydentate conjugated-carbon chain ligands are called carbolong complexes, which are expected to have interesting properties. In this work, the preparation of 12-carbon carbolong complexes in which all of the coordinated atoms in the equatorial plane are carbon atoms was studied. With the help of the well-established mechanism, a new approach to prepare coplanar carbolong complexes bearing different organic functional groups was developed by adding different terminal alkynes in sequence. In the presence of HBF , these coplanar carbolong complexes were converted to η -allyl osmapentalene derivatives, which can be produced directly from the reaction of cyclopropaosmapentalene 1 with terminal alkynes in the presence of AgBF under anhydrous conditions. This study offers a new route for the preparation of functional osmium carbolong complexes with excellent photothermal properties, which can be used to prepare photothermal materials.

“…Metalla‐analogues of conventional organic aromatic compounds, in which a transition metal and its ancillary ligands formally replace one carbon atom, have attracted considerable interest recently . Although the isolation and study of a considerable number of metallabenzenes and fused‐ring metallabenzenes has been reported, much remains to be explored regarding the reactivity of these compounds.…”

Section: Introductionmentioning

confidence: 99%

Syntheses of Amino‐Substituted Iridabenzofurans and Subsequent Selective N‐Functionalisation

Frogley

Perera

Wright

2017

Self Cite

The first examples of amino-substituted fused-ring metallabenzenes, the cationic iridabenzofuran [Ir(C H O{NH -2}{OMe-7})(CO)(PPh ) ][O SCF ] (5) and neutral analogue Ir(C H {NH -2}{OMe-7})Cl(PPh ) (6), can be prepared by reduction of the corresponding nitro-substituted iridabenzofurans with zinc and concentrated hydrochloric acid. N-functionalised derivatives of 5 and 6 are formed through alkylation, sulfonylation or acylation. Thus, consecutive treatments with methyl triflate and base gives the corresponding trimethylammonium-substituted iridabenzofurans while sulfonamide derivatives are formed with p-toluenesulfonyl chloride. N-Acylation of 5 or 6 with acid chlorides, however, selectively form either amide or imide products depending on the charge on the metal and the steric size of the acid chloride. Cationic 5 gives amide substituted products regardless of the conditions whereas neutral 6 rapidly undergoes di-N-acylation with excess benzoyl chloride under mild conditions to give the imide-substituted product Ir(C H O{N[C(O)Ph] -2}{OMe-7})Cl(PPh ) (13). Selective mono-acylation of 6 can be achieved with one equivalent of benzoyl chloride or with excess of the sterically congested pivaloyl chloride.