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تعداد نتایج: 4028368 فیلتر نتایج به سال:
in the present of methylimidazolium hydrogen sulfate, the synthesis of arylidene heterobicyclic pyrimidinones is studied by condensation of aromatic aldehyde, cyclopentanone, and urea or thiourea. using solvent-free conditions, non-toxic and inexpensive materials, simple and clean work-up, short reaction times and good yields of the products are the advantages of this method.
for the first time lactic acid was applied as an efficient and green catalyst for the one-pot three-component synthesis of amidoalkyl naphthols via the condensation between arylaldehydes, 2-naphthol and amides or urea under thermal solvent-free conditions in good to excellent yields. we have demonestrated a mild and efficient eco-friendly tandem synthesis of amidoalkyl naphthols using lactic ac...
An improved, simple, and facile synthesis of 3,4-dihydropyrimidin-2(1H)-ones by employing three-component, one-pot condensation reaction of β-keto ester, aromatic aldehydes, and urea or N-methylurea using LaCl3/ClCH2COOH as an inexpensive and green chemistry catalyst system under solvent-free conditions described. Compared with the classicalBiginelli reaction conditions, this method has the adv...
The availability of inexpensive computers and the popularity of the World Wide Web ("Web") have encouraged the development of inexpensive, readily available software that enable secure financial transactions over the Web. This same "e-commerce" technology consisting of database-backed web sites, web-based forms, secure communications and digital signatures can be used for securely reporting and...
For the first time lactic acid was applied as an efficient and green catalyst for the one-pot three-component synthesis of amidoalkyl naphthols via the condensation between arylaldehydes, 2-naphthol and amides or urea under thermal solvent-free conditions in good to excellent yields. We have demonestrated a mild and efficient eco-friendly tandem synthesis of amidoalkyl naphthols using lactic ac...
For the first time lactic acid was applied as an efficient and green catalyst for the one-pot three-component synthesis of amidoalkyl naphthols via the condensation between arylaldehydes, 2-naphthol and amides or urea under thermal solvent-free conditions in good to excellent yields. We have demonestrated a mild and efficient eco-friendly tandem synthesis of amidoalkyl naphthols using lactic ac...
an improved, simple, and facile synthesis of 3,4-dihydropyrimidin-2(1h)-ones by employing three-component, one-pot condensation reaction of β-keto ester, aromatic aldehydes, and urea or n-methylurea using lacl3/clch2cooh as an inexpensive and green chemistry catalyst system under solvent-free conditions described. compared with the classicalbiginelli reaction conditions, this method has the adv...
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