A rapid, efficient, and high-yielding synthesis of 4,4′-(arylmethylene)bis(3-methyl-1H-pyrazol-5-ol) derivatives catalyzed by 12-tungstophosphoric acid (H3PW12O40)
A rapid, efficient, and high-yielding synthesis of 4,4′-(arylmethylene)bis(3-methyl-1H-pyrazol-5-ol) derivatives catalyzed by 12-tungstophosphoric acid (H3PW12O40)
作者:Asieh Vafaee、Abolghasem Davoodnia、Mehdi Pordel
DOI:10.1007/s11164-014-1896-y
日期:2015.11
A fast, green, and efficient method for high-yielding synthesis of 4,4′-(arylmethylene)bis(3-methyl-1H-pyrazol-5-ols) by one-pot reaction of two equivalents of 3-methyl-1H-pyrazol-5(4H)-one with aryl aldehydes, using 12-tungstophosphoric acid (H3PW12O40) as an effective and inorganic catalyst is described. The catalyst is inexpensive and readily available and can be recovered conveniently and reused efficiently such that a considerable catalytic activity still could be achieved after the tenth run. Compared to the other methods, the present methodology offers several advantages such as excellent yields, short reaction times, and mild reaction conditions with an easy work-up.