نتایج جستجو برای: diketone

تعداد نتایج: 518  

Journal: :Berichte der deutschen chemischen Gesellschaft 1884

Journal: :Berichte der deutschen chemischen Gesellschaft 1885

A convenient synthetic method for the synthesis of 2,4,5-trisubstituted and 1,2,4,5-tetra substituted imidazole derivatives, has been developed via one-pot condensation reaction in solvent-free condition when aldehyde, ammonium acetate/amine, and 1,2-diketone are reacted using 0.8 mol% of NP-LaMnO3 at 80 °C under solvent free conditions. Catalyst could be recovered and reused in five reaction c...

The synthetic route in this work is based on the classical Friedel-Crafts strategy, and began with 1,4-dimethoxybenzene (I), followed by alkylation and selective demethylation of 2-methoxy function in 0x0-acid (3). The orthoformylation to synthesize aldehyde (6) was based on the Reimer-Tieman reaction. Chain extension of this aldehyde required methylation of the hydroxyl group and condensat...

Journal: :Synlett : accounts and rapid communications in synthetic organic chemistry 2010
Nolan T McDougal Scott C Virgil Brian M Stoltz

The use of high-throughput screening allowed for the optimization of reaction conditions for the palladium-catalyzed asymmetric decarboxylative alkylation reaction of enolate-stabilized enol carbonates. Changing to a non-polar reaction solvent and to an electron-deficient PHOX derivative as ligand from our standard reaction conditions improved the enantioselectivity for the alkylation of a keta...

Journal: :Chemical & pharmaceutical bulletin 2012
Masateru Ono Yoshinari Takaki Masamitsu Takatsuji Kousuke Akiyama Masafumi Okawa Junei Kinjo Hiroyuki Miyashita Hitoshi Yoshimitsu Toshihiro Nohara

Three new resin glycosides, quamoclins V (1), VI (2), and VII (3) and a new tetrahydropyran derivative, quamopyran (4), were isolated from the seeds of Quamoclit pennata BOJER (Convolvulaceae). The chemical structures of these compounds were determined primarily on the basis of spectroscopic data. The carboxyl group of the aglycone, 11S-convolvulinolic acid, of 1 and 2 was linked intermolecular...

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