Carbonylative Coupling of 4,4’-Diiodobiphenyl Catalyzed by Pd(NHC) Complex

Abstract

To develop a luminescent material with high color purity, luminous efficiency, and stability, we synthesized diketone by carbonylative Suzuki coupling in the presence of Pd(NHC) complex as the catalyst. Carbonylative coupling of 4,4'-diiodobiphenyl and phenylboronic acid was investigated to study in detail the catalytic ability of the Pd(NHC) complex. Reactions were carried out using both CO and metal carbonyls. Bis-(1,3-dihydro-1,3-dimethyl-2H-imidazol-2-ylidene) diiodo palladium was used as the catalytic complex. Reaction products biphenyl-4,4'-diylbis (phenylmethanone) 3 and (4'-iodobiphenyl-4-yl)(phenyl) methanone 4 were obtained as a result of CO insertion into the palladium(II)-aryl bond. However, when pyridine-4-yl boronic acid was used in place of phenylboronic acid as the starting reagent, synthetic reaction yielding 3 and 4 were found not to occur.

Palladium Catalyzed Carbonylative Coupling for Synthesis of Arylketones and Arylesters Using Chloroform as the Carbon Monoxide Source

“…The reaction of 4,4′-diiodo-1,1′-biphenyl with (4-ethylphenyl) boronic acid yielded the monocarbonylated product, (4-ethylphenyl)­(4′-iodo-[1,1′-biphenyl]-4-yl)­methanone ( 3ab ) exclusively in 64% yield. This is in contrast to the previous report on carbonylative Suzuki coupling of 4,4′-diiodo-1,1′-biphenyl using a CO balloon or metal carbonyls and a Pd­(NHC) complex, where a mixture of mono- ( 3ab ) and dicarbonylated products [biphenyl-4,4′-diyl bis­(phenyl­methanone)] was obtained in varied yields . This method, therefore, offers better selectivity for synthesizing the monocarbonylated ketone derivatives.…”

“…It begins with the oxidative addition of aryl­(heteroaryl)­iodide on Pd(0)­L 2 to yield complex I , which undergoes insertion of carbon monoxide generated in situ from chloroform and KOH to form complex II . Thereafter, a phenyl anion or phenoxide ion generated from arylboronic acid­(pinacol ester) or phenol, respectively, undergoes ligand displacement, resulting in the formation of complex III . , …”

Advances in Transition‐Metal Catalyzed Carbonylative Suzuki‐Miyaura Coupling Reaction: An Update

“…Two years later in 2013, Lee et al [16] . reported a carbonylative Suzuki coupling of 4,4′‐diiodobiphenyl 9a and phenylboronic acid 9b with detail investigation of catalytic behaviour of Pd−NHC complex.…”

Tetra- and Dinuclear Palladium Complexes Based on a Ligand of 2,8-Di-2-pyridinylanthyridine: Preparation, Characterization, and Catalytic Activity

“… Initial tests investigated the effect of the CO source on the model reaction. It is known that the carbon monoxide source dramatically affects the efficiency of carbonylation. , Quite often, the carbonylative coupling reactions perform in the presence of high pressure of CO or metal carbonyls. By using complex 2 as the catalyst, the carbonylative coupling reaction of PhI with tolueneboronic acid in a mixed solvent (CH 3 CN/H 2 O) proceeded smoothly to give I in good yields, either under atmospheric pressure of CO or with the use of a stoichiometric amount of Mo­(CO) 6 , but showed poor selectivity for Cr­(CO) 6 or W­(CO) 6 (Table , entries 1–4).…”