DABCO as a novel and efficient catalyst for the synthesis of 4(3H)-quinazolinone derivatives

4(3H)-Quinazolinones were synthesized in high to excellent yields through the one-pot condensation of anthranilic acid, trimethyl orthoformate and primary amines in the presence of DABCO under solvent free conditions.KEY WORDS: 4(3H)-Quinazolinone, DABCO (1,4-diazabicyclo[2,2,2]octane), Trimethyl orthoformate, Anthranilic acid Bull. Chem. Soc. Ethiop. 2011, 25(2), 305-308

Copper-catalyzed cyclization reaction: Unique synthesis of condensed thiazoles and selenazoles

587-58

Improved battery life for context awareness application in smart-phones

The new smart-phones with new operating system and portable sensors support the basis for context awareness systems and applications for handling user activity and user privacy. Nowadays, individuals need new services and real time information anywhere and anytime. Context awareness is an emerging service, which could be able to improve the user experiences in current situation. Context awareness can be considered as location, calendar, user activity and etc. The review of the literature proves that context awareness in mobile phone can be useful and studied as unavoidable service in next generation of smart-phone applications. In this paper, a short review about context awareness in mobile phone is studied, furthermore, we critically analyzed related works of context awareness in smart-phones. The review shows that the most important context in mobile phone is location, which is mostly obtained by using Global Positioning System (GPS) sensor in mobile phones but GPS can significantly increases battery consumption in mobile phones. In this regard, a framework as Improved Battery life in Context Awareness System (IBCS) is proposed to improve battery life and reduce cost of using GPS in context awareness applications based on smart-phones. The review argues the weakness and strength of these studies, and aims to (a) indicate the most important context in mobile phone, (b) reduce the battery consumption of GPS sensor in mobile phone

Solvent-free synthesis of xanthene derivatives by Preyssler type heteropolyacid

Dimedone reacted with aromatic aldehydes and 3,4-methylenedioxyphenol or β-naphthol in the presence of a catalytic amount of Preyssler type heteropolyacid, H14[NaP5W30O110], as a green and reusable catalyst under solvent-free conditions to form a variety of  new xanthene derivatives in very good  yields.KEY WORDS: Xanthene derivatives, Solvent-free synthesis, Preyssler type heteropolyacid, 3,4-Methylene dioxyphenol, β-Naphthol, Three-component one-pot reactions Bull. Chem. Soc. Ethiop. 2011, 25(3), 399-406

Synthesis of some new 3,7–disubstituted thiazolo[3,2-c]pyrimidin-5-one

694-69

Cellulose Sulfonic Acid: An Efficient Heterogeneous Catalyst for the Synthesis of 1, 8-Dioxo-octahydroxanthenes

1,8-Dioxo-octahydroxanthenes have been synthesized good yields via a reaction of aldehydes and dimedone in the presence of cellulose sulfonic acid as a heterogeneous catalyst under solvent-free condition

Solid-state induced heterocyclization under microwave irradiation: Synthesis of 2-phenyl-3-hydroxy-quinolin-4(1<i>H</i>)-one

779-781Synthesis of 2-phenyl-3-hydroxy-quinolin-4(1H)-one under microwave irradiation in solventless system has been described. The mechanism of the reaction is also discussed

Direct oxidative deprotection of trimethylsilyl ethers with cerium ammonium nitrate supported onto HZSM-5 zeolite under microwave irradiation in solventless system

813-814Trimethylsilyl ethers are selectively and rapidly oxidized to the corresponding carbonyl compounds by cerium ammonium nitrate (CAN) supported onto HZSM-5 zeolite under microwave irradiation in solvent-free conditions