Pyrididine–Carboxylate Ligands as Double‐Bridge Spacers in Cu^I Metallacycles

Abstract

The addition of pyridine‐3‐carboxylic acid (3‐PyCOOH), (E)‐3‐(pyridin‐3‐yl)acrylic acid (3‐PyCH=CHCOOH), or 3‐(pyridin‐4‐yl)benzoic acid (3‐PyPhCOOH) to the Lewis acidic [Cu(dppf)(NCMe)2][BF4]·2MeCN·2H2O [1·2MeCN·2H2O, dppf = 1,1′‐bis(diphenylphosphanyl)ferrocene] in the presence of NEt3 afforded the complexes [Cu2(dppf)2(3‐PyCOO)2]·3CHCl3 (2·3CHCl3), [Cu2(dppf)2(3‐PyCH=CHCOO)2]·CH2Cl2·C6H14 (3·CH2Cl2·C6H14), and [Cu2(dppf)2(3‐PyPhCOO)2]·CH2Cl2 (4·CH2Cl2) with a common metallomacrocycle core and doubly bridging pyridine–carboxylate ligands as spacers. These dinuclear complexes have been structurally characterized by single‐crystal X‐ray crystallography, and their emission activities have been studied.

Synthesis, Structure and Cu‐Phenylacetylide Coordination of an Unsymmetrically Substituted Bulky dppf‐Analog

“…Similarly, a bathochromic shift was observed in the emission maximum which is located at 524 nm with a quantum yield of 1.3 %. Although the quantum yield is very limited compared with other luminescent Cu(I)‐complexes (e. g. quantum yields of selected complexes at room temperature and in solid state are enlisted as follows: Cu 4 I 4 (PPh 3 ) 4 (44 %), [10u] [Cu 2 (dcpm) 2 (CH 3 CN) 2 ](BF 4 ) 2 (26 %), [10y] [Cu 2 (dcpm) 2 ](BF 4 ) 2 (42 %), [10y] [(CuI) 3 (dcpm) 2 ] (11 %), [10y] [(Trip‐C≡C)Cu] 8 (21 %)], [10z] where dcpm and Trip stand for bis(dicyclohexylphosphano)methane and 2,4,6‐triisopropylphenyl, respectively], it is nevertheless remarkable for a ferrocene‐based complex, as reports on luminescent ferrocene complexes with transition metals are extremely rare [2a,23] …”

Bulky 1,1′-bisphosphanoferrocenes and their coordination behaviour towards Cu(i)

“…Fc′(PCl 2 ) 2 , MesLi•LiBr•OEt 2 , and dppf•Cu(MeCN) 2 BF 4 were synthesized by following the procedure reported in the literature. 56,57,103,104 Mes 2 PX (X = Cl/Br, 48%/52%; Fig. S1 and S2 in ESI file ‡) was synthesized by following the procedure reported for Xyl 2 PX (X = Cl, Br).…”

Isolable Cu(I) Complexes of Extremely Electron-Poor, Completely Unreduced o-Quinone and “Di-o-Quinone” Ligands Stabilized through π–π Interactions in the Secondary Coordination Sphere

“…19 F NMR (400 MHz, CD 2 Cl 2 ): δ = −62.9 ppm. The crystal structure of a compound [Cu­(dppf)­(CH 3 CN) 2 ]­(BF 4 ), which has a different counteranion, was reported previously …”

“…The crystal structure of a compound [Cu(dppf)(CH 3 CN) 2 ](BF 4 ), which has a different counteranion, was reported previously. 42 ■ ASSOCIATED CONTENT * S Supporting Information…”