octane (DABCO)-catalyzed Knoevenagel condensation reactions, which showed better catalytic activity compared to other ionic liquid (IL) that had no hydroxyl group attached to the IL scaffold. The effect of hydrogen bond formation between the hydroxyl group of [HyEtPy]Cl and the carbonyl group of aldehyde played an important role in the Knoevenagel condensation reaction. In the [HyEtPy]Cl–H2O–DABCO
A novel catalyst-economic strategy with a recovered palladium catalyst was successfully applied for multi-task and maximum reuse in different types of one-by-one downstream reactions, from catalytic hydrogenation to Suzuki and Sonogashira-type cross-coupling reactions, Knoevenagel condensations, and trans-Knoevenagel-like condensations.
New synthetic protocol for stereoselective synthesis of diethyl 1,2-dicyano-3-alkyl-(aryl)cyclopropane-1,2-dicarboxylate
作者:Nader Noroozi Pesyan、Saeed Golizadeh
DOI:10.1007/s13738-015-0590-3
日期:2015.7
A new, fast and straightforward method for the one-pot reaction of aromatic and aliphatic aldehydes and dialdehydes with ethyl cyanoacetate and cyanogen bromide was developed to afford stereoselectively diethyl 1,2-dicyano-3-alkyl/arylcyclopropane-1,2-dicarboxylate in excellent yields and short reaction time (about 5 s). The structures were characterized by IR, 1H NMR and 13C NMR spectroscopy. The reaction mechanism was discussed.
Abstract A simple and efficient Knoevenagelcondensationmethod for the synthesis of trisubstituted electrophilic alkenes was developed using lipase as a biocatalyst. Knoevenagelcondensation was performed using the conventional method and using lipases (Aspergillus oryzae or Rhizopus oryzae) as biocatalysts, and reaction time, reaction temperature, yield, and recyclability were compared. Using a lipase
Copolymerizable methine and anthraquinone compounds and articles containing them
申请人:Pearson Clay Jason
公开号:US20060115516A1
公开(公告)日:2006-06-01
This invention relates to polymerizable ultraviolet light absorbers and yellow colorants and their use in ophthalmic lenses. In particular, this invention relates to polymerizable ultraviolet light absorbing methine compounds and yellow compounds of the methine and anthraquinone classes that block ultraviolet light and/or violet-blue light transmission through ophthalmic lenses.