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Five organic solvents, N-methyl-2-pyrrolidone (NMP), cyclohexanone (CYC), N,N-dimethyl­formamide (DMF), acetonitrile (ACN), and toluene (TOL) were used to treat Shenhua direct coal liquefaction residue (DCLR) by swelling processes. The treated residues were characterized by swelling degree (Q), SEM, FTIR, TG-DTG, and Py-GC/MS methods. The effect of swelling treatment on the swelling properties, surface morphology, functional group distribution, and pyrolysis performance of the residues was investigated. Swelling results showed that the swelling effect with different solvents on each residue was different and that the swelling degree of the residue treated by NMP was high, 2.4. Swelling treatment could significantly change the surface morphology and pore structure of DCLR, resulting in the increase of pores in the residue. FTIR spectra proposed that swelling treatment could effectively break the hydrogen bonds in residue and change the abundance of oxygen-containing functional groups. TG-DTG profiles demonstrated that the swelling procedure could increase the weight loss and pyrolysis rate of the residue, and the pyrolysis activation energy in high-temperature region (≥360 °C) was obviously reduced, while the energy in the low-temperature region (120–360 °C) was increased. Py-GC/MS proposed that the swelling pretreatment could change the pyrolysis product distribution of the residue, with the species of the products decreased, and that ketones and arenes compounds were the main products.

The direct regio- and enantioselective C6 functionalization of 2,3-disubstituted indoles with azadienes has been developed using chiral phosphoric acid as catalyst, providing a convenient approach to synthesize the optically active heterotriarylmethanes with excellent yields, broad substrate scope, and up to 98% ee. Mechanistic studies revealed that N-alkylation of 2,3-disubstituted indoles with azadienes would be reversible, and enantioselective C6 functionalization could be enabled.

N -methyl-2-pyrrolidone (NMP), pyridine (Py), tetrahydrofuran (THF), and tetralin (THN) were used to swell Hefeng acid-washed bituminous coal (HBC AC ). The swelling effect on HBC AC by each solvent is different, among which NMP presented well swelling performance, with a swelling degree of 2.11. FTIR results showed that acid washing and swelling processes presented a marginal effect on HBC, and there was no damage to the macromolecule structure of the coal. TG–DTG profiles of the swollen coals illustrated that the total weight loss of each sample was lower than that of the acid-washing one, while the temperature of the maximum weight loss rate peak was almost unchanged, around 445 °C. Extract yield by methanol followed the order of HBC AC > HBC > HBC AC–NMP (swelled by NMP), showing that acid washing promoted the methanol extraction process, with a higher extract yield of 3.21%, which is twice that of HBC (1.66%).