The 2-amino-5-nitropyridine (2A5NP) is a weak Bronsted base that gains protons from strong or medium acids in acidic solution at the pH <2. The 2A5NPP compound was synthesized by mixing 1:1 proportions of 2-amino-5-nitropyridine (Merck) and p-phenol sulfonic acid (Sigma-Aldrich) in Millipore water with the resistivity of 18.2 MΩ. cm. After mixing of 2A5NP and p-phenol sulfonic acid, the complete dissolution took place. Then, the solution was stirred well using a magnetic stirrer to get homogeneous at 50°C. The prepared solution was filtered twice and it allowed to dry at room temperature. The resultant material was washed several times with ethanol to remove unreacted starting materials. Then, the purity of the synthesized material was improved …show more content…
During this reaction, three kinds of intramolecular bonding are formed between 2A5NP+ cation and aromatic sulfonate (SO3-) anion. One is pyridinium salt bridge (PyN+-Hb…Oa-S) between the pyridinium cation and the aromatic sulfonate (SO3-) anion. The second one is hydrogen bond (N-Ha...Ob-S) between pyridine amino group to aromatic sulfonate (SO3-) group. The third one is additional hydrogen bond between (N-Hb…-Oc-S and N-Hb-Oa-S) neighboring sulfonate anions to form a continuous binding chain along a-axis. The p-phenol sulfonic acid also has additional binding site between (Ar-O-H…-Ob-S-Ar) hydroxyl group to neighboring aromatic sulfonic anions. The distances of salt bridge and hydrogen bonds are in the ranges of 1.7-1.9 and 1.9-2.4 Å, respectively [structure]. The reaction mechanism of the title compound is presented in Figure …show more content…
The crystallizations are not observed in DMF containing solvent due to the high viscosity nature of the solution. However, the spurious nucleation was observed during slow evaporation by methanol. The calculated amount of title material was dissolved in methanol solvent and stirred for 5 hours to maintain homogeneity at 50°C. The saturated solution was overheated upto 55°C and kept for 5 hours in constant temperature water bath to prevent the formation of secondary nucleation. During this process, the solution containing beaker was tightly covered by polyethene cover to control the solvent evaporation. The solution was cooled upto 50°C by 1°C /h until nucleation occurred. Single crystals of 2A5NPP were grown from saturated solution by the slow cooling method in the cooling rate of 0.01°C/h from 50°C to 35°C. During this process, the pH of the solution was kept as 1.7. Finally, the optically transparent single crystal of dimensions 10×4×4 mm3 was harvested after a typical period of 60 days. The as-grown crystals are shown in figure (8). Various solvents like water, ethanol, acetone, methanol, acetic acid, acetonitrile and tetrahydrofurans have been tried in slow evaporation solution technique (SEST) for the growth of title crystal. We have found methanol is a suitable solvent to grow crystal to a reasonable size. The slow cooling method was adopted
The goal of this two week lab was to examine the stereochemistry of the oxidation-reduction interconversion of 4-tert-butylcyclohexanol and 4-tert-butylcyclohexanone. The purpose of first week was to explore the oxidation of an alcohol to a ketone and see how the reduction of the ketone will affect the stereoselectivity. The purpose of first week is to oxidize the alcohol, 4-tert-butylcyclohexanol, to ketone just so that it can be reduced back into the alcohol to see how OH will react. The purpose of second week was to reduce 4-tert-butylcyclohexanol from first week and determine the effect of the product's diastereoselectivity by performing reduction procedures using sodium borohydride The chemicals for this lab are sodium hypochlorite, 4-tert-butylcyclohexanone
This experiment was conduct to investigate the fluorescent behaviour of Leucophor PAF and to investigate the quenching of QBS with NaCl. It was found that the Leucophor PAF indeed satisfied the characteristic to act as whitening agent. It was also found that the quenching of QBS with NaCl was a diffusion-controlled collision process.
This paper describes the methods used in the identification, investigation of properties, and synthesis of an unknown compound. The compound was identified as calcium nitrate by a variety of tests. When the compound was received, it was already known to be one of twelve possible ionic compounds. The flame test identified the presence of the calcium anion in the compound. The compound tested positive for the nitrate cation using the iron sulfate test. At this point it was hypothesized that the compound was calcium nitrate. Reactivity tests and quantitative analysis comparing the unknown compound with calcium nitrate supported this hypothesis. Synthesis reactions were then carried out and analyzed.
As shown in equation 2, the reaction between the phosphonium salt and the sodium hydroxide produces the ylide/carbanion that is stabilized due to the positive charge on phosphorus and the conjugation that occurs in the benzene ring as shown by the structure B in equation 2. The ylide produced also has a resonance form (B’). The resonance form is advantageous because it contains no formal charge and the double bond it contains results in the same position of the double bond in the final a...
A weak peak was at a position between 1600-1620 cm-1 can also be seem in the IR, which was likely to be aromatic C=C functional group that was from two benzene rings attached to alkynes. On the other hand, the IR spectrum of the experimental diphenylacetylene resulted in 4 peaks. The first peak was strong and broad at the position of 3359.26 cm-1, which was most likely to be OH bond. The OH bond appeared in the spectrum because of the residue left from ethanol that was used to clean the product at the end of recrystallization process. It might also be from the water that was trapped in the crystal since the solution was put in ice bath during the recrystallization process. The second peak was weak, but sharp. It was at the position of 3062.93 cm-1, which indicated that C-H (sp2) was presence in the compound. The group was likely from the C-H bonds in the benzene ring attached to the alkyne. The remaining peaks were weak and at positions of 1637.48 and 1599.15 cm-1, respectively. This showed that the compound had aromatic C=C function groups, which was from the benzene rings. Overall, by looking at the functional groups presented in the compound, one can assume that the compound consisted of diphenylacetelene and ethanol or
The identity of the product was trans-2,3-dibromo-3-phenylpropanoic acid, and it was concluded to be this from melting point data. This product resulted from an Anti Addition mechanism.
The goal of this lab is to synthesize maleic anhydride with polyethylene glycol of 200g/mol molecular weight (PEG 200) and 2,3-dimethyl-1,3-butadiene to get 4,5-dimethylcyclohexane-1,2-dicarboxylic acid anhydride and its diacid by using Diels-Alders reaction and hydrolysis, respectively. The crystals were determined using melting point determination and IR spectroscopy.
In this lab 4-tert-butylcyclohexanone is reduced by sodium borohydride (NaBH4) to produce the cis and trans isomers of 4-tert-butylcyclohexanol. Since the starting material is a ketone, NaBH4 is strong enough to perform a reduction and lithium aluminum hydride is not needed. NaBH4 can attack the carbonyl group at an equatorial (cis) or axial (trans) position, making this reaction stereoselective. After the ketone is reduced by the metal-hydride, hydrochloric acid adds a proton to the negatively charged oxygen to make a hydroxyl group. The trans isomer is more abundant than the cis based on the results found in the experiment and the fact that the trans isomer is more stable; due to having the largest functional groups in equatorial positions.
"Chemistry Lesson 1 Instruction, Page 5." Chemistry Lesson 1 Instruction, Page 5. N.p., n.d. Web. 15 Jan. 2014.
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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 isomerization procedure was done in order to create dimethyl fumarate from dimethyl maleate. Dimethyl maleate and dimethyl fumarate are cis and trans isomers, respectively. This procedure was done via a free radical mechanism using bromine. The analysis of carvones reaction was done in order to identify the smell and optical rotation of the carvone samples that were provided. The odor was determined by smelling the compound and the optical rotation was determined using a polarimeter.
Haynes, William M.., and David R. Lide. CRC handbook of chemistry and physics a ready-reference book of chemical and physical data : 2012-2013. 93e édition. ed. Boca Raton (Fla.): CRC Press, 2012. Print.
Heterocyclic compounds are of particular importance as they are associated with a wide variety of physiological activities. A good number of synthetic and naturally occurring heterocyclic systems find use in medicine, dyes, pesticides, agrochemicals, polymers etc. Heterocyclic systems are important building-blocks for new materials possessing interesting electronic, mechanical or biological properties and a number of its derivatives have been marked as valuable commercial products.
Development of specific ethers has been inactive and fruitful area of investigation in the past few decades.2The strategy of ether catalysis General encompasses synergistic activation of a ethers an electrophile by two or more reactive centers through the combination of a Lewis acid and Lewis base working in concert. Such approach results in high reaction rates and excellent ethers. Hydrogen bonding plays a crucial role in this catalysis. Hydrogen bonding to an electrophile decreases the electron density of this species, activating it toward nucleophilic attack. Recently chemists have begun to appreciate the tremendous potential offered by hydrogen bonding as a tool for electrophile activation in synthetic catalytic systems. In particular, ethers donors have emerged as a broadly applicable class of catalysts for ethers synthesis. An amide unit, the key functional group of peptides, plays an important role in catalyst design and modification. Based on the understanding of different asymmetric catalytic reaction mechanisms, the creation of amide structure-based ether and was realized by rational arrangement of hydrogen-bond networks. According to their model, two water molecules simultaneously establish H-bonds to the carbonyl oxygen of the substrate for optimal transition state stabilization. The concept of explicit double H-bonding activation was no longer restricted to one type of reaction or catalyst, but became a generally applicable principle. The simultaneous donation of two hydrogen bonds has proven to be a highly successful strategy for electrophile activation. Such interactions benefit from increased strength and directionality compared to a single hydrogen bond. Ethers containing double hydrogen bond ethers are capable of directing the assembly of molecules with similar control as