Pd catalyzed coupling of 1,2-dibromoarenes and anilines: formation of N,N-diaryl-o-phenylenediamines

Palladium-catalyzed formation of secondary and tertiary amines from aryl dihalides with air-stable ferrocenyl tri- and diphosphines: Synthesis and X-ray structure of efficient catalysts beyond [PdCl2(DPPF)]

“…Interestingly, it appears thus that the coupling of the second equivalent of aniline to the intermediate monobromodiarylamine is much slower than the addition of the first equivalent of 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 7 aniline to the 1,2-dibromobenzene. This is in contrast to previously reported results using the airsensitive electron-rich monophosphine P(t-Bu) 3 [31].…”

“…However, encouraging screening experiments indicated that with 1 mol% of *PdCl(η 3 -C 3 H 5 )] 2 and 2 mol% of DPPF, the use of toluene as solvent, at 100 °C, in the presence of 1.4 equiv of t-BuOK as base, selectively led to the conversion of 1,2-dibromobenzene (2a) into 2-bromodiphenylamine (3a) in about 30% yield. This amount of palladium and ligand is five to ten times lower, with conditions generally milder, than the current syntheses for the coupling of comparable substrates [28][29][30][31][32][33]. Under these conditions of base, solvent and temperature, the performances of phosphines L2 to L9 were also examined and compared to DPPF (Table 1).…”

Synthesis, characterization, molecular structures, cytotoxic and antibacterial activities of N,N′-diaryl-o-phenylenediamines

“…Chemicals were commercial available and used as received. The compounds 1 and 3 were readily synthesized by coupling reaction of the corresponding aryl amines with 1,2-dibromobenzene [15]. synthetic route [17].…”

“…On the other hand, Hartwig and Buchwald have been developed an efficient synthetic methods to carry out a coupling reaction between 1,2-dibromoarenes and anilines [13,14]. In order to carry out a structural modification on phenylene diamines, Harlan et al reported a simple catalyzed coupling reaction to isolated N,N-diaryl-o-phenylenediamine derivatives [15]. Base on that, in this paper, we describe the molecular structure and their biological activity of a short series of N,N 0 -aryl-o-phenylenediamines (Scheme 2) such as N,N 0 -2,6-dimethylphenyl-o-phenylenediamine (1), N,N 0 -2,4,6-trimethylphenyl-o-phenylenediamine (2), and N,N 0 -2,6-diisopropylphenyl-o-phenylenediamine (3).…”

Selective Reduction of Carbonyl Amides: Toward the First Unsymmetrical Bischelating N‐Substituted 1,2‐Diamino‐4,5‐di­amidobenzene

“…[2] Class II (2) contains amino substituents at the 2-and 5-positions of the benzoquinoid ring (R 1 = or ϶ R 2 = or ϶ R 3 ). [1,[3][4][5][6][7][8][9][10][11] Class III derivatives (3) contains all other 1,4-benzoquinonediimines (X = or ϶ Y, but both are different from N). [1] The second class of quinonediimines is the largest owing to easy access to symmetrical systems (R 1 = R 2 = R 3 ) and a high stability, which have allowed their use in different fields ranging from hair coloring [12] and biosensors [13] to supramolecular [14] and coordination chemistry.…”