Chapter-2 Efficient ZnO NPs catalyzed Friedlander annulations in the synthesis of diverse quinolin-2(1H)-ones 2.1.1 INTRODUCTION OF QUINOLINONES AND QUINOLINES The quinolinone and quinoline ring is highly prevalent in natural compounds. There are synthetic and potential agents, which show various pharmacological properties (Priya et al., 2012). Quinolinones are important structural intermediates for synthesis of functionalized quinolines (Baston et al., 2000). Quinolines have demonstrated various applications such as biomedical (Ridley et al., 2002), fungicides (Oliva et al., 2003), virucides (Liu et al., 1997), biocides (Sabatini et al., 2013), alkaloids (Fournet et al., 1993) rubber chemicals and flavoring agents (Jones et al., 1996). They …show more content…
There are numerous methods on quinolinone synthesis have been reported (Liu et al., 2012). Still, Friedlander reaction remains simplest and the finest method, various methods have been listed by Jose et al., (Jose et al., 2009 & Maguire et al., 1994) for the synthesis of quinolines and quinolinones. Friedlander annulations are carried out in aqueous or alcoholic solutions in the presence of a base or acid under reflux conditions at 150 - 220 °C. Though, the aforementioned synthetic strategies involve unsafe conditions, expensive palladium or phosphine reagents and lower yields, in addition to ending up with quinoline derivatives instead of quinolinones. Hence, it is very essential to overcome these difficulties and to find simple process for the synthesis of quinolin-2(1H)-one. We paved the way to develop inexpensive, solvent free, simple process, less hazardous, Eco-friendly, highly efficient Friedlander annulations of aminobenzophenones reaction with different 1,3-diones (with active hydrogen) in the presence of ZnO NPs (Scheme 1). Although, there are many reports on ZnO NPs in organic conversion reactions (Krishnakumar et al., 2012). Synthesized the ZnO NPs by using existing procedure (Siva Kumar et al., 2013) and Characterized by XRD, SEM,
The sole purpose of performing the lab was to utilize aldol condensation reactions to synthesize a cyclopenta-dienone, while using UV spectrophotometry and computer visualization to further understand the dienone. In the beginning of the lab, the tetraphenylcyclopentadienone (TPCP) was synthesized using dibenzyl ketone and benzyl under extremely basic conditions. The synthesis process could be further understood by observing the mechanism portrayed in Figure 1. According to the figure, the dibenzyl ketone will first loose an alpha hydrogen to form the enolate intermediate.
yield of the pure product was determined to be 95.42%. PURPOSE The purpose of this lab was to perform an electro-philic aromatic substitution and determine the identity of the major product. TLC was used to detect unreacted starting material or isomeric products present in the reaction mixture. RESULTS The theoretical yield of the m-nitrobenzoate was determined to be 4.59 grams.
The purpose of the experiment was to study the kinetics of the hydrolysis of ester, p-nitrophenyl acetate (NPA) that is catalyzed by the buffer imidazole (Im). In terms of kinetics, specifically speaking, the rate of reaction as determined by the concentration, reaction orders, and rate constant with each species in a chemical reaction. By using the concentration of the catalyst and the temperature, the overall reaction rate was determined. The rate constants of K0, Kobs, and Kcat can be derived via the plotting of the absorbtion at 400nm of p-nitrophenol vs. the concentration of the catalyst imidazole. Lastly, the free energy of activation, ΔGǂ, that is necessary to force the reactant’s transformation of the reactants to the transition state structure will be determined by using the equation ΔGǂ = ΔHǂ – TΔSǂ derived from the Eyring plot.
Strychnine is a poisonous alkaloid, C21H22N2O2, obtained in colorless or white rhombic crystals. These have a bitter taste and melt at around 290( C (4 p.1). Alkaloids are any class of naturally occurring organic nitrogen containing bases, usually containing one or more of these nitrogen atoms in a ring of atoms called a cyclic system. Alkaloids are primarily found in plants and are predominant in flowering plant species. The function of alkaloids in plants is thought to be simply a waste product of the plants metabolic processes, but current research may suggest a specific biological function. This is evident in some plants as the levels of alkaloid increase just prior to seed formation and then drops off after the seed is ripe. This evidence suggests possible mechanisms of maturation and possible defense, against certain insect species (5 p.2). Strychnine, being an alkaloid, is slightly soluble in water, but is more soluble in alcohol and is released from its salts by alkalis. Many of the commercial alkaloids are found in the genus Strychnos.
The bark of cinchona produces several alkaloids. The most important alkaloid, quinine, has certain febrifuge properties. Quinine was used in the battle against malaria since the 1630's. Of 38 species of cinchona, four species have economic value for the production of quinine: C. calisaya, C. legeriana, C. officianalis and C. succirubra.
First we gathered and labeled 6 test tubes, five for the compounds and one for the control, which was water. We used 5 compounds with 3 replicates per compound to accurately measure the responses to the different inhibitor concentrations. We added 2 drops of inhibitor in tubes 1-5. Then we added 5mL of distilled water in tubes 1-6 and 8 drops of potato extract. We used potato extract because of its ability to produce benzoquinone.
Figure 2: Formation of 1,1-Diphenylethanol with Grignard Reagent Afterwards, the Grignard reagent was added to acetophenone to form 1,1-diphenylethanol. Ammonium chloride was added to protonate the oxyanion (acid workup). Results and Discussion Figure 3: Grignard Reaction Mechanism
Medicinal or Pharmaceutical Chemistry is a scientific discipline at the intersection of chemistry and pharmacology involved with designing, synthesizing and developing pharmaceutical drugs. Medicinal chemistry involves the identification, syntheses and development of new chemical entities suitable for therapeutic use. The majority of the therapeutic agents are heterocyclic compounds; hence heterocyclic chemistry has become the most prolific area for drug discovery. Based upon the fact, the present investigation was planned and substantial interest has been shown in the synthesis and characterization of various substituted novel (1, 3) benzothiazole heterocyclies derivatives in search of potential drugs.
Can the reaction between an alcohol and a carboxylic acid produce an ester that has a strong, pleasant odour?
Strychnine is a naturally occurring drug that exists as a colorless, odorless, bitter, and highly toxic crystalline alkaloid used in killing small vertebrates such as rodents, birds, and other pests. Barks and seeds from climbing shrubs and trees from the genus Strychnos contain the potent alkaloid, and the distribution of the plants occurs widely distributed in warm climates across Africa, Asia, and America. The Strychnos nux-vomica and Strychnos ignatii plants found in Australia and southern Asia are the main sources of the strychnine alkaloid. However, scientists have discovered methods of synthetically producing the drug in laboratories. Strychnine has a chemical formula of C21H22N2O2 and a molar mass of 334.41g/mol, and the compound
According to Pollard et al. (2014), The purpose of this study was to determine the degree of integration of QSEN competencies and learning strategies in nursing programs in New York State. The implementation of (QSEN) in nursing programs is the most important because it guides teaching future nursing professionals to raise the quality and safety of health services.
Chemistry has lots of charming facts; one such is hetero cyclic compounds. Heterocyclic compounds are organic compounds that contain a ring structure containing atoms in addition to carbon, such as sulfur, oxygen or nitrogen as the heteroatom. The ring may be aromatic or non-aromatic. Every first step of life starts with hetero-cyclic compounds. Every man's potential to think, intelligence, behavior, character depends on his gene. The basic skeleton of the genetic material (DNA) is made up of heterocyclic compound like adenine, guanine, cytosine and thymine. Thus knowing about heterocyclic compound and its application is part of venturing human life. The different pharmacological activity of the different hetero cyclic compounds ring , from a last related to this moiety and screened them for their different pharmacological activities to get a molecule which have good pharmacological activity and lesser side effect. These pharmacological activities of new hetero cyclic derivatives this hetero cyclic has shown its importance as antibacterial, antifungal, anti-inflammatory, hypoglycemic, antidepressant, anti-malarial, analgesic, anticancer
Natural products, in general terms, are chemical substances produced in nature1. Or simply putting it, they are molecules found in living organisms, according to Mcmurry2. Natural products are secondary metabolites, which are small molecules living in the organism without effecting in a major way, like nucleus acids, which are essential for the survival of the organisms19. While many of them don’t have a specific biological role, some of them act as sex attractants and anti-feedants19. They differ with other biological micro molecules in their complexity, since they are much smaller than average micro molecule, tend to be more diverse and have the ability to conserve themselves for a long period of time even without a specific biological activity or role19. The importance of natural products relay on its variety of uses, since natural products are used in pharmaceutical industry, food production and pesticides3. The techniques commonly used to produce natural products are: Column chromatography, extraction and distillation. In this paper, the efficiency of the extraction method in synthesizing natural products will be evaluated. Extraction of natural products in an economic and environmentally-friendly way is of high importance to all industries involved.
Organic chemistry is the best and most interesting branch of chemistry. There are five branches of chemistry: analytical, biochemistry, physical, inorganic, and organic chemistry. However organic chemistry is the largest branch, most intriguing, and has a large impact on everyone around the world. It is the study of carbon compounds and deals with the structure, reactions, and properties of organic compounds and materials. It plays a huge role in manufacturing many products that people use everyday. “Organic chemistry explores how to change and connect compounds based on carbon atoms in order to synthesize new substances with new properties” (Chemistry). There are millions of organic compounds, much more than inorganic, and new compounds
Global warming and climate change has induced a worldwide awareness to reduce the toxic & hazardous waste materials, thus, the green synthesis route have raised actively the progress in the fields of science and industry (Ahmad et al., 2011). Therefore, biological sources such as bacteria, fungi, yeasts, algae and plants can materials catalyzed specific reaction as a part of modern and realistic biosynthetic strategy. The current prospective on biological system has created a commercial importance due to their enzymatic reactions, photochemical characteristics and herbal