A facile and practical method that the copper powder-catalyzed Ullmann amination of aryl halides with aqueous methylamine under organic solvent- and ligand-free condition at 100 °C and in air gave N-arylamines as sole products in good to excellent yields. The presence of a small amount of air is essential. Other aliphatic primary amines show good to very high reactivity. Secondary amines and aniline are not reactive. Sensitive substituents (i.e., CHO, MeCO, CN and Cl) are tolerable in the reaction.

A facile and efficient self-sorting assemble (CSA) strategy has been paved for bottom-up construction of the 3-fold symmetrical and highly substituted hexa-cata-hexabenzocoronenes (c-HBCs), the trithieno analogues, and larger disc-shaped PAHs from simple chemicals using benzylic carbons as tenon joints and a novel FeCl3-mediated AAA process as a key step. The structures of the as-prepared c-HBCs and related NGs were clearly identified by spectral analyses and X-ray crystallographic studies. Moreover, these can be envisaged to serve as new launching platforms for the construction of larger and more complex π-conjugated molecules and supramolecular architectures because of the modifiable and symmetrical decorations.

Experimental Section1 H and 13 C NMR spectra were recorded on a Bruker DRX 300 spectrometer in CDCl 3 , and tetramethylsilane (TMS) was used as internal standard. The structures of the synthesized materials were confirmed by TEM using a JEM-3010 transmission electron microscope operating at an accelerating voltage of 300kv. Histograms of particle size distribution of Pd nanoparticles were obtained from the TEM images by measuring more than 200 particles in each sample. The surface area of the catalysts was determined from full nitrogen adsorption and desorption isotherms at 77K using a Sorptometer ST-03A. The catalysts were outgassed for four hours at 573K prior to measurements. Infrared spectra were recorded with a FT-IR Bruker EQUINX-55 Spectrometer equipped with a KBr beam splitter and a TGS detector. The chemical analyses of the content of palladium, respectively, were carried out with an ICP-OES (inductively coupled plasma-optical emission spectrometer) Vista (Varian). The samples (amount of about 10 mg) were digested in a mixture of 1.5 mL of HCl (37%), 0.5 mL of HNO 3 (65%), and 1 mL of HF (40%) by heating.Generally, the solutions were diluted to a volume of 50 mL using a volumetric flask. EDXA measurements were performed on a Philips-FEI Quanta 200 scanning electron microscope. This apparatus was equipped with a Si-Li energy dispersive, quantitative chemical analysis was performed for Si and Pd. C, H and N elemental analysis were performed on a Perkin-Elmer 2400 CHN elemental analyzer. The powder XRD pattern of SiO 2 -BisILs[PF 6 ]-Pd 0 (2c) was recorded on a Rigalcu D/Max-3c X-ray diffractometer (Cuka, Ni filter). Gas chromatography was performed on an Agilent GC 6890N with a FID detector equipped with an DB-35 column (30 m long, 0.25 mm inner diameter). Parameters were as follows: initial temperature 70 ℃; initial time 3 min; ramp 8 ℃•min -1 ; final temperature 180 ℃; final time 2 min; injector temperature 220 ℃;detector temperature 250 ℃; injection volume 1.0 µL. The high boiling point substrates and the products were analyzed by using HPLC. All hydrogenated products were initially identified using authentic commercial samples of the expected products. Melting point is uncorrected.Materials. PdCl 2 (AR grade), imidazole (AR grade), sodium borohydride (AR grade), 1-chlorooctane (AR grade), KPF 6 , silica gel (surface area, 385 m 2 g -1 ), nitrobenzene, 4-nitrophenol, 2-nitrophenol and other aromatic nitro compounds were used as received. 1,4-dibromobutane and 3-chloropropyltriethoxy silane, purchased from Alfa Aesar. All organic solvents (toluene, methanol, ethanol, and so on.) were dried under standard purification conditions.

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An efficient and reusable catalyst with PdEDTA immobilized in an ionic liquid brush and a green procedure have been developed for coupling aryl iodides and bromides with phenylboronic acid. These reactions were conducted in water under aerobic conditions with water-insoluble or even solid aryl halides. The protocol has the advantages of excellent yields, environmental friendliness, and catalyst recyclability. There was no apparent loss of catalyst efficiency until the 10th cycle.