16857-95-7Relevant academic research and scientific papers
Quantification of the Lewis Basicities and Nucleophilicities of 1,3,5-Tris(dialkylamino)benzenes
Micheletti, Gabriele,Mayer, Robert J.,Cino, Silvia,Boga, Carla,Mazzanti, Andrea,Ofial, Armin R.,Mayr, Herbert
, p. 6347 - 6357 (2021/11/01)
Equilibrium constants for the formation of Wheland complexes from 1,3,5-tris(dialkylamino)benzenes and benzhydrylium ions (Ar2CH+) have been determined photometrically in dichloromethane solution at 20 °C. The Lewis basicity of the r
First isolation of a Wheland intermediate in the azo-coupling reaction, its X-ray crystal structure determination and products from its evolution
Boga, Carla,Del Vecchio, Erminia,Tozzi, Silvia,Forlani, Luciano,Monari, Magda,Micheletti, Gabriele,Zanna, Nicola
, p. 51 - 66 (2014/04/17)
The reaction between tris(N-piperidinyl)benzene and 4- methoxybenzenediazonium tetrafluoroborate afforded a Wheland intermediate (W) that was isolated and crystallized at low temperature. This permitted to obtain, for the first time, the X-ray structure analysis of a σ- complex in the diazo coupling reaction. In solution, W slowly evolves to the rearomatized product PH+ (as salt). The single crystal X-ray diffraction determination of the neutral azo compound P is also reported. ARKAT-USA, Inc.
Nickel-catalysed sequential amination of aryl- and heteroaryl di- and trichlorides
Desmarets, Christophe,Schneider, Rapha?l,Fort, Yves
, p. 7657 - 7664 (2007/10/03)
Unsymmetrical 1,3-diaminobenzenes and diaminopyridines were efficiently prepared by reaction of 3-chloroanilines and chloroaminopyridines with amines via a nickel-catalysed amination. The Ni/2,2′-bipyridine catalyst is also effective for the sequential am
Synthesis of 2,3-dihydroindoles, indoles, and anilines by transition metal-free amination of aryl chlorides
Beller,Breindl,Riermeier,Tillack
, p. 1403 - 1412 (2007/10/03)
Aliphatic and aromatic amines react with 2- and 3-chlorostyrene in the presence of potassium tert-butoxide to give N-substituted 2,3-dihydroindoles in good yields. The combination of this domino-amination protocol with a suitable dehydrogenation reaction gives access to pharmacologically interesting indoles in a one-pot procedure. Overall product yields of N-substituted indoles > 50% are obtained by this method starting from commercially available substrates. In addition to the intramolecular base-promoted amination of aromatic C-Cl, bonds, metal-free intermolecular aminations of aryl chlorides with primary and secondary amines are described. The use of potassium tert-butoxide as base allows the synthesis of various anilines in good to excellent yields. Due to the formation of aryne intermediates, either N-substituted anilines or meta-substituted anilines are produced with excellent selectivities.
Nickel-mediated amination chemistry. Part 1: Efficient aminations of (het)aryl 1,3-di and 1,3,5-trichlorides
Desmarets, Christophe,Schneider, Rapha?l,Fort, Yves
, p. 2875 - 2879 (2007/10/03)
The first Ni-catalysed synthesis of di- and triamino substituted benzenes and diamino substituted pyridines from the corresponding aryl chlorides and amines is described. (C) 2000 Elsevier Science Ltd.
Synthesis, Structure, and Spectral Behavior of Donor-Acceptor Substituted Biphenyls
Effenberger, Franz,Agster, Wolfgang,Fischer, Peter,Jogun, Kurt H.,Stezowski, John J.,et al.
, p. 4649 - 4658 (2007/10/02)
Reaction of the activated halonitrobenzenes 2a-f with the bis- and tris(dialkylamino)benzenes 1a-e affords, via a direct nucleophilic substitution, the highly substituted biphenyls 3a-o; the lesser substituted biphenyls 5 and 6 were prepared by an Ullmann reaction.All these biphenyls are deeply colored; the dark red color can be assigned to an intramolecular charge transfer.A crystal structure determination was carried out for 2,4,6-tripyrrolidino-2',4',6'-trinitrobiphenyl (3a): space group C2/c, a = 16.071 (2) Angstroem, b = 14.545 (1) Angstroem, c = 20.177 (2) Angstroem, β = 91.361 (9)deg, Z = 8 (temperature ca. 120 K).The dihedral angle between the two arene rings was found to be only 52.5 deg, despite the four bulky substituents in the o,o'-positions.With this far-from-orthogonal torsional angle about the biphenyl linkage, the strong intramolecular charge transfer from the ? system of the donor into the ? system of the acceptor arene becomes easily understandable.A PPP calculation with the torsional angles taken from the X-ray structure analysis satisfactorily reproduces the experimental absorption spectrum of 3a.The shift of the long-wavelength absorption between the individual biphenyls 3a-o, 5, and 6 likewise is accounted for satisfactorily by the calculation; it depends primarily on the intrinsic donor strength of the different NR2 moieties (pyrrolidino > dimethylamino > piperidino > morpholino).The 1H NMR spectra (in dilute solution) likewise mirror this gradation in NR2 donor capacity; they also show that steric hindrance at the biphenyl linkage is mainly the result of interaction between the o-dialkylamino groups and the C6 skeleton of the acceptor arene.This is borne out by the crystal structure analysis.
