The reaction the occurred in the experiment was a reaction between acetic acid and isopentyl alcohol to form isopentyl acetate and water. The esterification of acetic acid with isopentyl alcohol occurs in four steps. The first step in the reaction mechanism is the protonation of acetic acid with a proton from the concentrated sulfuric acid that was added to the reaction mixture. In the second step, acetic acid reacts with the isopentyl alcohol to form a reaction intermediate which undergoes proton transfer or rearrangement protonation. Water acts as a leaving group in the third step and is removed from the reaction intermediate.
Since alkenes are immiscible with concentrated HBr, tetrabutylammonium bromide is used as a phase-transfer catalyst. It forms a complex with HBr and extracts it from the aqueous phase into the organic phase where the alkene is. This dehydrates the acid, making it more reactive so that the addition reaction is possible. Rapid stirring is required in order to maximize the surface area
The nucleophilic attack pushes the carbonyl electrons onto the carbonyl oxygen, which forms a short-lived intermediate. The third step is where the oxyanion electrons reform the bond with the aromatic amino acid. Then the bond between the carboxyl-terminus of the amino acid and the n-terminus of the residue is cleaved and its electrons are used to take out the hydrogen of the nitrogen on the Histidine 57. The c-terminal side of the polypeptide is free to dissociate form the active site. Step four is basically just where water can now enter and bind to the active site through hydrogen bonding, which is between the hydrogen atoms of water and the Histidine-57 nitrogen.
When tin chloride is added to the solution, Sn2+ took away positive charged ions; Fe3+ to Fe2+ (2Fe3+(aq) + Sn2+(aq) → 2Fe2+(aq) + Sn4+(aq)). This took away Fe3+ from the solution, causing the equilibrium to change to the reactants to balance the concentration of Fe2+. The solution turned a lighter color to increased rate of the reverse reaction. When AgNO3 was added to the solution, the silver nitrate broke down into Ag+ and
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). The resonating ylide will react with the electrophilic carbonyl carbon of its aromatic aldehyde to produce a betaine intermediate, or a crystalized 4
An electrophile means an electron seeking species. Haloarenes will undergo the usual benzene ring reactions such as nitration, halogenation, Friedel-Crafts reactions and sulphonation. Before discussing all the electrophilic reactions, we need to understand the nature of Reaction of Haloarenes with respect to the attack of an electrophile. We know that haloarenes are electron-rich compounds. Therefore, they can undergo electrophilic substitution reaction and the attacking species, in this case, will be an electrophile.
Squalene undergoes a two-step cyclization to yield lanosterol catalyzed by sequalene mono-oxygenase and sequalene 2, 3 epoxidase enzymes. Sequalene mono oxygenase is the second committed step in cholesterol biosynthesis and lead to the formation squalene 2, 3 epoxide. This enzymatic reaction require supernatant protein factor (SPF) and NADPH as a cofactor to introduce molecular oxygen as an epoxide at the 2, 3 position of squalene. The activity of supernatant protein factor itself is regulated by phosphorylation/dephosphorylation (Singh et al., 2003). Through a series of 19 additiona lreactions, lanosterol is converted to cholesterol.
The difference in this chemical and physical properties will aid in their separation. Processes like solubility, gravitational filtration and recrystallization will be used to separate the substances present in Panacetin. The melting and boiling point of the substances will help in concluding on which of these compounds will be presented at the end of experiment. Procedure and observation The Panacetin content was weighed approximately 3.0493g and transferred to the Erlenmeyer flask; 75ml of dichloromethane (CH¬2CL2) was added to the content. The dichloromethane (CH2Cl2) dissolved the sucrose, leaving the active unknown agent and aspirin behind.
Hydrogen gas was generated during the reaction which was seen when bubbles were formed as the penny was dissolved into the beaker. An error that could have been present during the lab includes not letting the zinc react completely with the chloride ions by removing the penny too early from the solution. For instance, the percent error of this lab was 45.6%, which was determined by the subtraction of the theoretical percent of Cu 2.5% and the experimental percent of Cu 3.64% and dividing by the theoretical percent of Cu 2.5%. This experiment showed how reactants react with one another in a solution to drive a chemical reaction and the products that result from the
After that, it undergoes process transesterification where the dimethyl ester reacts with ethane-1,2-diol and cause ethane-1,2-diol exchanges for methanol. Polymerization of the monomer. Figure 2.4 represent the condensation reaction where the monomer undergoes polycondensation process with the elimination of ethane-1,2-diol. This process requires antimony (II) oxide which acts as the catalyst and conducted at high temperature and low pressure when the monomer and the polymer are molten. The ethane-1,2-diol is recycled.