in the present work, the effect of ca(no3)2.4h2o and (nh4)2hpo4 primary solutions as the beginning materials in synthesis of a calcium phosphate phase, was examined. so, we investigated the wet chemical reactions in solution at different temperatures by a hydrothermal condition aimed at hydroxyapatite (ca10(po4)6(oh)2); (hap) synthesis. the powders were investigated by xrd,sem, fe-tem, hrtem, e...

A facile and efficient synthesis of bis(indolyl)methanes derivatives (3a-u) was reported via a condensation reaction of aldehydes and indole in the presence of by silica-supported-3-(triethoxysilyl) propane-1-ammonium chloride catalysis under solvent free conditions. We studied the reaction in different conditions and optimized. The use of just 0.02 g of (silica gel-ammonium salt) is sufficient...

Nano sulfated titania was tested as solid acid heterogeneous catalyst for the synthesis of 4-(Trifluoromethyl) coumarin and coumarin derivatives under solvent-free condition. Factorial design evidenced a positive effect of reaction temperature, amount of catalyst, and solvents.  This nano-sized sulfated titania has been prepared by a sol-gel hydrothermal process. The prepared sulfated titania s...

an efficient one-pot condensation for the synthesis of 1,8-dioxo-octahydroxanthene is  achieved through a condensation of aryl aldehydes and 5,5-dimethyl-1,3-cyclohexandione in the presence of  nbs. this method enjoys several advantages such as low cost, simple work up procedure and safe reaction condition. in addition, water was chosen as a green solvent.

4-dodecylbenzenesulfonic acid (dbsa) has been shown to be an efficient, mild, green, stable and chemoselective brønsted acid catalyst for the synthesis of 1, 1-diacetates (acylals) of aldehydes under solvent-free conditions. the mild condition, eco-friendly, excellent yields, short reaction times and using an easily available, inexpensive and reusable catalyst are important features of this met...

Nano sulfated titania was tested as solid acid heterogeneous catalyst for the synthesis of 4-(Trifluoromethyl) coumarin and coumarin derivatives under solvent-free condition. Factorial design evidenced a positive effect of reaction temperature, amount of catalyst, and solvents.  This nano-sized sulfated titania has been prepared by a sol-gel hydrothermal process. The prepared sulfated titania s...