Efficient and one-pot synthesis of 1,8-dioxo-octahydroxanthenes was described by Knoevenagel condensation, Michael addition and cyclodehydration of dimedone. This reaction was carried out through condensation of dimedone and various aromatic aldehydes in the presence of task-specific Brønsted acidic ionic liquid under solvent free conditions. The catalyst could be recycled five times without si...

Efficient and one-pot synthesis of 1,8-dioxo-octahydroxanthenes was described by Knoevenagel condensation, Michael addition and cyclodehydration of dimedone. This reaction was carried out through condensation of dimedone and various aromatic aldehydes in the presence of task-specific Brønsted acidic ionic liquid under solvent free conditions. The catalyst could be recycled five times without si...

one of the major criticisms leveled at task-based language teaching (tblt), despite its countless merits, is developing fluency at the cost of accuracy. the post-task stage affords a number of options to counteract this downside through task repetition and task recycling. these two options are considered to positively affect learners' oral performance in terms of fluency, accuracy, and complexi...

koenenite=[mg7ai4(oh)22]4+.[na4(ca,mg)2ci12]4- , is a typical non-silicate clay mineral of oceanic salt deposits which also widely occurs in salt clay, anhydrite, halite, and potash-bearing rocks. koenenite is found as an undesirable sludge-forming component in the processing of potassium salts . koenenite was first reported, in 1902, as an impurity in a fairly pure halite from the justus! pota...