The reactions of iodobenzene with azole compounds, 1,2-disubstituted imidazoles and 2-substituted oxazoles and thiazoles, were examined in the presence of catalytic amounts of Pd(OAc)2 and PPh3 in DMF using alkali metal carbonates as bases. It was found that the coupling products, 5-arylazoles, could be selectively produced in good yields by using Cs2CO3. In the case that their 2-position is unsubstituted, the site could also be arylated. In reactions using bromobenzene in place of iodobenzene, K2CO3 was also as effective as Cs2CO3. The addition of a stoichiometric amount of CuI appeared to specifically promote the reactions of thiazoles as well as those of thiophene derivatives. The reactions of 2-unsubstituted azole compounds with aryl iodides could be mediated by CuI to some extent without using the palladium species to give 2-arylazoles.

formed without an organic solvent, an important ecological advantage. In this case the functionalization of the silica with the correct balance of polyethers is critical (Figure 3). Use of hydrophilic PEO yielded only low rates and conversions. Nonloo 10% PEO/iO%PPO-SiOz iit rn 20%PEOSiOz 75 3E mol% 25 0

The electrochemically stable and relatively high conductive room temperature molten salts (RTMS) have been obtained with the use of small ammonium cations such as methoxymethyltrimethylammonium and bis(trifluoromethylsulfonyl)imide. The RTMS showed high conductivity (4.7 mS cm−1 at 25 °C) which is the highest value of all the ammonium based RTMS reported so far.

N-(2‘-Phenylphenyl)benzenesulfonamides react with acrylate esters accompanied via cleavage of the C−H bond at their 2‘-position in the presence of a catalyst system of Pd(OAc)2 and Cu(OAc)2 and a base under air to produce 5,6-dihydro-5-(benzenesulfonyl)phenanthridine-6-acetate derivatives in high yields. The reactions of benzoic acid with butyl acrylate and styrene can also give 3-[(butoxycarbonyl)methyl]phthalide and 3-phenylisocoumarin, respectively.

The structural characteristics of a pentane-insoluble asphaltene isolated from the vacuum residue of an Arabian crude mixture have been investigated by pyrolysis gas chromatography/ mass spectrometry (py/GC/MS), 1 H/ 13 C NMR, gel permeation chromatography (GPC), and matrixassisted laser desorption/ionization time-of-flight (MALDI TOF) mass spectrometry. Assignments of NMR signals of the asphaltene have been discussed briefly on the basis of the information from the literature and compared with those of an aliphatic fraction isolated from the ruthenium ion catalyzed oxidation products of the asphaltene. The comparison data indicated that aliphatic substitution 〉C 1 on aromatics are little; however, most of the chain methylene groups are located within a polymeric-saturated fraction of the asphaltene. The average size of aromatic fused ring systems has been determined to be 4-5 for the sample. Pyrolysis tests implied that the asphaltene sample is constructed with relatively large polycyclic units connected by relatively strong bonds. Our results also support a view that asphaltene is the mixture of complex polydispersed molecules with large variation of molecular sizes.

No abstract

No abstract

Secondary 2-thiophenecarboxamides efficiently undergo unique triarylation accompanied by formal decarbamoylation under palladium catalysis. 3-Substituted thiophenes, especially having an electron-withdrawing group, can also be triarylated.