Ring opening reactions of N-sulfonyl aziridines by primary and secondary amines in silica gel (SG)-water system were achieved, which provided a mild, practical and environmentally benign method to synthesize mono- and bis-sulfonyl substituted amines. When primary and secondary amines were used in excess, they reacted with N-sulfonyl aziridines smoothly at room temperature, mainly affording 1:1 ring opening products. Reactions of primary amines with 2 equiv. of aziridines produced 2:1 ring opening products. Some 1:1 products can be cyclized with CS₂ to synthesize N-sulfonyl cyclothioureas also in water.

The reactions of N-substituted saccharins and phthalimides with amines were promoted by water. Various o-sulfamoyl benzamides and N,N′-disubstituted phthalamides were prepared in moderate to good yields. These reactions have prominent advantages, such as short reaction time, less by-products and simple isolation of the products. Water can probably stabilize the reaction intermediates and facilitate precipitation of the ring-opening products. When steric hindrance arose, hydrolytic compounds, either free acid or salts of the acids, were obtained. Possible reason for the formation of amine salts of o-sulfamoyl benzoic acids was proposed.

In this article, we report the synthesis and herbicidal activities of sulfonylureas bearing the 1,3,4-thiadiazole moiety. The target compounds 9a, 9b, 9c, 9d, 9e, 9f, 9g, 9h, 9i, 9j, 9k, 9l were synthesized using 2-hydrazinocarbonyl benzenesulfonamide (4) and phenyl pyrimidinecarbamates as starting materials. The key intermediate, 2-(4,5-dihydro-5-thioxo-1,3,4-thiadiazol-2-yl)benzenesulfonamide (5), was prepared from 4 and CS₂ via a conventional method or an improved method. The improved method, in which sulfonamido group acts as a directing group for the cyclization reaction, is more concise and efficient. The structures of the target compounds were determined by IR, ¹H-NMR, ¹³C-NMR, MS, and elemental analysis. Their herbicidal activities were screened by Petri dish tests and pot tests. As the results, sulfonylureas 9h and 9j inhibited Brassica napus, Amaranthus retroflexus, and Echinochloa crusgalli at the 15 g/ha level, which is at the same level as azimsulfuron. Moreover, the safety tests showed that 9j was safe to wheat at dosage of 60 g/ha and might develop further into a herbicide in wheat field.

Graphite oxide (GO) has attracted much attention of material and catalysis chemists recently. Here we describe a combination of GO and molecular sieves for the dehydrogenative aromatization. GO prepared through improved Hummers method showed high oxidative activity in this reaction. Partially or fully saturated aromatic compounds were converted to their corresponding dehydrogenated aromatic products with fair to excellent conversions and selectivities. As both GO and molecular sieves are easily available, cheap, lowly toxic and have good tolerance to various functional groups, this reaction provides a facile approach toward aromatic compounds from their saturated precursors.

A sequential one-pot synthesis of N-sulfonylcyclothioureas from N-monosulfonyl diamines, CS₂ and chloroacetic acid at room temperature in water is described. In the absence of highly toxic thiophosgene and organic solvents, this method is environmentally benign. Simple reaction conditions, easy purification of the products, good yields and thioglycolic acid as the useful byproduct are also important attributes of this methodology. The plausible mechanism including tandem reactions is proposed.