A simple and efficient method for the synthesis of quinolines and polycyclic quinolines using Li+ modified nanoporous Na+-montmorillonite is described. This new nanocatalyst proceeds via Friedlander annulation under solvent-free conditions. It describes our observations about a trend of catalytic activity of Lithium cation in nanoporous Na+-montmorillonite. In this study, several types of 1,3-d...

The massive and automated access to Web resources through robots has made it essential for Web service providers to make some conclusion about whether the "user" is a human or a robot. A Human Interaction Proof (HIP) like Completely Automated Public Turing test to tell Computers and Humans Apart (CAPTCHA) offers a way to make such a distinction. CAPTCHA is a reverse Turing test used by Web serv...

a simple and efficient method for the synthesis of quinolines and polycyclic quinolines using li+ modified nanoporous na+-montmorillonite is described. this new nanocatalyst proceeds via friedlander annulation under solvent-free conditions. it describes our observations about a trend of catalytic activity of lithium cation in nanoporous na+-montmorillonite. in this study, several types of 1,3-d...

Cellulose sulfuric acid was used as an efficient biopolymer-based catalyst for the synthesis of tetrahydropyrimido[4,5-b]quinoline-2,4,6-triones and hexahydro-2H-pyrazolo[5,4-b]quinoline-6-ones via three component reaction of aldehyde, 5,5-dimethyl-1,3-cyclohexadione and 6-amino-1,3-dimethyluracil or 5-amino-3-methyl-1-phenypyrazole under solvent-free conditions at 90 oC. The major advantages o...

Cellulose sulfuric acid was used as an efficient biopolymer-based catalyst for the synthesis of tetrahydropyrimido[4,5-b]quinoline-2,4,6-triones and hexahydro-2H-pyrazolo[5,4-b]quinoline-6-ones via three component reaction of aldehyde, 5,5-dimethyl-1,3-cyclohexadione and 6-amino-1,3-dimethyluracil or 5-amino-3-methyl-1-phenypyrazole under solvent-free conditions at 90 oC. The major advantages o...

A convenient, efficient and practical procedure for the synthesis of 1-amidoalkyl 2-naphthols is described by condensation of aromatic aldehydes with amides and 2-naphthol in the presence of P2O5/SiO2 as an efficient catalyst. Moreover, in the present of this catalyst, the synthesis of 14-aryl or alkyl-14H-dibenzo[a,j]xanthenes is studied by co...

A convenient, efficient and practical procedure for the synthesis of 1-amidoalkyl 2-naphthols is described by condensation of aromatic aldehydes with amides and 2-naphthol in the presence of P2O5/SiO2 as an efficient catalyst. Moreover, in the present of this catalyst, the synthesis of 14-aryl or alkyl-14H-dibenzo[a,j]xanthenes is studied by co...

a facile and efficient method for the preparation of 1,1-diacetates of aldehydes is improved. the acidified kaolin with sulfuric acid (2 % w/w) catalyzed 1,1-diacetates formation from aldehydes in solvent-free conditions. both aromatic and aliphatic aldehydes gave high yields (85-95 %) of the corresponding 1, 1-diacetates. advantages of this method are the use of inexpensive and selective catal...

The educational experience of students in a Computer Engineering capstone design course can be greatly enhanced by providing a framework that enables students to design devices that are accessible over the web. The framework consists of inexpensive hardware and software that permits the connection of arbitrary devices to a web page. Remote users can then interact with the physical device throug...