Introduction:- In organic chemistry the substitution reactions is the most important reactions, especially Nucleophilic aromatic substitution reactions where nucleophile attacks positive charge or partially positive charge As it does so, it replaces a weaker nucleophile which then becomes a leaving group. The remaining positive or partially positive atom becomes an electrophile. The general form of the reaction is: Nuc: + R-LG → R-Nuc + LG: The electron pair (:) from the nucleophile (Nuc :) attacks the substrate (R-LG) forming a new covalent bond Nuc-R-LG. The prior state of charge is restored when the leaving group (LG) departs with an electron pair. The principal product in this case is R-Nuc.
Danielle Pitter CHEM 137 Professor D’Amelia 3/1/17 Extraction of a Neutral Compound from Acid and Base Impurities Discussion: The diethyl ether solvent is nonpolar; therefore, based on the expression like dissolves like, other nonpolar molecules will dissolve in it. The 9-fluorenone is a nonpolar molecule; therefore, it will dissolve in the nonpolar diethyl ether. The benzoic acid has a polar carboxyl group; however, the ring is nonpolar. The nonpolar ring in the benzoic acid is what makes it soluble in the diethyl ether. The ethyl-4-aminobenzoate is similar to benzoic acid, in that it has a nonpolar ring and has polar attachments.
Since ferrocene is highly reactive (due to its two cyclopentadienyl rings), AlCl3 can be replaced with a more benign catalyst, phosphoric acid. This reaction will also use acetic anhydride in place of an alkyl halide. Figure 2 shows the mechanism for this
The Wittig reaction is valuable reaction. It has unique properties that allows for a carbon=carbon double bond to form from where a C=O double bond used to be located. Creating additional C=C double bonds is valuable due to its use in synthesis. The Wittig reaction will allow the synthesis of Stilbene (E and Z) from a Benzaldehyde (Ketcha, 141). One purpose of a Wittig reaction is the formation of alkenes from aldehydes or ketones employing a carbo-phosphorous ylide, which is stabilized vie resonance to allow for the carbon bonded to phosphorus to be deprotonate from by a base (Ketcha, 142).
This reaction was able to happen during designated lab time due to the fact that a phenol was used. Phenols or more reactive than unsubstitued benzene rings due to the presence of the alcohol on the benzene ring. The alcohol is considered an activating group due to the oxygen’s ability to donate its lone pairs into the benzene ring thus giving it more electrons and thus making it more nucleophilic and more likely to react with the introduced electrophilic species. As aforementioned, there are various products formed in this reaction the two major products formed though are the ortho and para products. It is debatable which product is more prominent due to steric reasons and the capability of each product to conduct in hydrogen bonding.
There chemical formation is C6,H12,O6 and due to their bond angles between the carbons, tend to form a pentose of hexoses, stable ring structure. Each carbon atom is then numbered 1-6 and depending on the orientation of the OH group in carbon 1 will decipher weather the monosaccharide is either an a or b
In step four α-ketoglutarate is oxidised to Succlnyl-CoA. It is oxidation decarboxylation step. It is catalysed by the enzyme α- Ketoglutarate dehydrogenase complex. This reaction is identical to the pyruvate dehydrogenase reaction. A five carbon sugar is reduced to a four carbon sugar.
This identified the product as luminol. 7. Discussion and Conclusion Carboxyl groups, which are made of a carbonyl group and a hydroxyl group, produce carboxylic acids when bonded to hydrogens, alkyls, or aryls. Replacing the hydroxyl group with a different heteroatom substituent will produce a carboxylic derivative, which include amides, anhydrides, esters, and nitriles. The polarity of the acyl carbon atom is produced by the substituent and the electronegativity of the C-O double bond.
CO2 (g) + 3H2 (g) CH3OH(g) + H2O (g) H25oC = -11.90 KJ/mol c.) CO2 (g) + H2 (g) CO (g) + H2O (g) H25oC = 41.01 KJ/mol The above three given chemical reactions are reversible reactions that is why we must have to control the temp., pressure and syngas mixture for the production of intermediate or products. And by observing the
ABSTRACT The Diels-Alder reaction has been an area of great research interest with regards to enhancing enantioselectivity in the reaction by use of various catalysts and reaction conditions. INTRODUCTION In organic chemistry, a Diels-Alder reaction refers to a 4, 2 cycloaddition between a diene consisting of alternating double bonds and a substituted alkene (the dienophile) resulting in a substituted cyclohexene system. The reaction is often used to reliably control regioselective and enantioselective aspects in organic synthesis. If specific conditions are applied, these reactions can be reversible, with the reverse reaction referred to as the retro-Diels-Alder reaction. Mechanism, Regioselectivity and Enantioselectivity of the Diels-Alder Reaction
Since all of the substituents are orth, para-directos, bromine in a bromination reaction would be substituted at either the 2 carbon, 4 carbon, 2 and 4 carbon, 2 and 6 carbon, or 2, 4, and 6 carbon. The more reactive the compound, the more substitution
Alcohols 1-Octanol, and 1-butanol were both found to be soluble in hexane while methyl alcohol was determined to be insoluble. when water was added to the different alcohols the opposite reaction occurred compared to hexane. 1-Octanol, and 1-butanol were both insoluble while methyl alcohol was the only soluble alcohol. 3.
Since xylene has a high boiling point of 140 °C, the reaction proceeded speedily. Crystallization of the product took place as the mixture underwent cooling. Filtration was used to isolate the product. The tests with regards to the melting point and spectra led to the determination that 9,10-dihydroanthracene-9,10-α,β-succinic anhydride was produced. The Diels Alder reaction is a high yield reaction and can be used to form as many as 4 carbons.
Explain why ethanal gives a positive iodoform test. • Ethanal is the only aldehyde to give a the positive result because the reaction requires a methyl group connected to a carbon atom with a keto or an OH- substituent. 2- In semicarbazone formation only one of the two –NH2groups in semicarbazide undergoes nucleophilic addition to the carbonyl group. Explain the difference in the reactivity of these two –NH2 groups, using resonance structures. • Within the semicarbazone formation there are two –NH2 groups.
According to the IR spectra received for the sample of Isopentyl Acetate, there were three main signals present. The first of the three signals was present at a wavenumber of 2,961.70 cm^-1. A signal at this wavenumber indicates that there are hydrogen-carbon bonds present in this sample of Isopentyl Acetate. According to the structural formula of Isopentyl Acetate, carbon-hydrogen bonds are indeed present in its structure. The second of the three signals was present at a wavenumber of 1,742.88 cm^-1 .