ipl-logo

Comparing Two Types Of Nucleophilic Na

809 Words4 Pages
bulb-icon

Recommended: Factors affecting reaction rate

There are two types of nucleophilic substitution: SN2 and SN1. The SN2 reaction mechanism is concerted meaning it involves only one step where the bonds of the leaving group and nucleophile are being formed and broken simultaneously1. The rate for this mechanism is dependent on both the concentration of the nucleophile and alkyl halide. The following figure displays the general mechanism for a SN2 reaction. The SN1 reaction mechanism is stepwise meaning that the leaving group departs first to create a carbocation intermediate, which later bonds with the nucleophile. The rate of this reaction is just dependent on the concentration of the alkyl halide.1 The following figure displays the general mechanism for a SN2 reaction. When comparing these two mechanisms’ rates, it is important to consider these factors: the structure of the alkyl halide, the leaving group, and the solvent. …show more content…

Since SN2 reactions require the nucleophile attacking the alkyl halide at the backside, the reaction can only happen if the empty orbital is accessible2. This means that if there are many groups close to the leaving group, then the reaction will be slower because the nucleophile will have a harder time accessing the alkyl halide. The less steric hindrance the alkyl halide has, the faster the reaction because there is less activation energy needed to overcome the steric hindrance2. For this reason, the rate of reaction is fastest on a primary carbon rather than a tertiary carbon because there is less steric hindrance on the primary carbon compared to the tertiary carbon. For this lab procedure, four alkyl halides are compared, and their structures are displayed down in the figure down

Show More
Related
2033 Words | 9 Pages

The hydrogen removed must be anti to the leaving group. The mechanism of E2 reaction has only one steps, which is displacement of leaving group by removing hydrogen. The rate of the E1 elimination is based on substrate only, while it depends on both substrate and base in E2 elimination. E1 elimination is favored by weak base and ptotic solvents, while E2 is favored by strong base, high concentration of nucleophile and aprotic solvents. The major product of E2 elimination is the more substituent alkene, while the products of E1 elimination are trans-cis alkene and terminal

Read More
881 Words | 4 Pages

Nevertheless, the effects caused by the breakage of bonds will eventually lead to a decrease in the rate of reaction. As seen in the data, the reaction rate increased from 0.088 to 0.101 throughout the interval of -5℃ to 20℃ then decreased to 0.037 throughout the interval 20℃ to 56℃. This can be explained by the fact that 20℃ is the optimal temperature, therefore the active site of the enzyme is complementary to the substrate, causing the rate of reaction to be

Read More
1039 Words | 5 Pages

In nucleophilic substitution reactions, there are two possibilities, either Sn1 or Sn2. In this particular experiment, an Sn2 reaction

Read More
1399 Words | 6 Pages

It is understood the mechanism is acid-catalyzed where protons coordinate with the carbonyl oxygen to make the carbonyl carbon more electropositive for nucleophilic attack (Scheme 1). In the experimental procedure all reactants were added together, this is inefficient as the protons can coordinate with either trans-cinnamic acid or methanol. Coordination with methanol is unnecessary as it reduces its nucleophilicity and makes less protons available to coordinate with the carboxylic acid. To improve

Read More
737 Words | 3 Pages

While the absolute value of slope of the graph for the solution containing only 0.5 mL mitochondrial suspension was 4 x 10-4, the slope of the graph for the solution containing 0.5 mL of mitochondrial suspension, 0.5 mL of 100 mM succinate, and 0.5 mL of 100 mM malonate was 7 x 10-4. Although this change is not large, it does demonstrate that the addition of TCA cycle intermediates has an impact on reaction rate. The decrease in the rate of reaction of the sample containing 0.5 mL of mitochondrial suspension, 0.5 mL of 100 mM succinate, and 0.5 mL of 100 mM malonate as compared to the sample with only 0.5 mL of mitochondrial suspension and 0.5 mL of 100 mM succinate shows that the addition of malonate inhibits the reduction of

Read More
247 Words | 1 Pages

The mechanism that is compatible with the rate law that is calculated is rate=k[I−][S2O8^ 2-], which matches with the b) mechanism. It starts with the slow step, which is the rate determining step and it also states that the rate law equals to rate=k[I−][S2O8^ 2-].

Read More
1111 Words | 5 Pages

In this test, primary halides precipitate the fastest while secondary halides need to be heated in order for a reaction to occur. Comparison of the rates of precipitation of the obtained product to standard 1° and 2° bromide solutions will show whether the product is a primary or secondary

Read More
387 Words | 2 Pages

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. The one closest to the ketone partakes in the electron resonance and therefore is the more stable out of the two. It doesn’t want to interrupt the p-orbital it’s sharing.

Read More
1766 Words | 8 Pages

Aims of experiment • Determine the rate constants for hydrolysis of (CH3)3CCl in solvent mixtures of different composition (50/50 V/V isopropanol/water and 40/60 V/V isopropanol/water) • Examine the effect of solvent mixture composition on the rate of hydrolysis of (CH3)3CCl Introduction With t-butyl chloride, (CH3)3CCl, being a tertiary halogenoalkane, it is predicted that (CH3)3CCl reacts with water in a nucleophilic substitution reaction (SN1 mechanism), where Step 1 is the rate-determining step. The reaction proceeds in a manner as shown

Read More
1653 Words | 7 Pages

=Describe two cellular processes that involve a covalent linkage between DNA and a protein. Answers: One method is called Strand Exchange mechanism where one of the single-strand 3ʹ ends from the damaged DNA molecule emerges its way into the template duplex and searches it for homologous sequences through base-pairing. Once the base pairing is established, DNA polymerase extends the invading strand by using the information provided by the undamaged template molecule, thus restoring the damaged DNA. This mechanism is achieved by interaction of a protein called Rad51 found in eukaryotes.

Read More
343 Words | 2 Pages

Nucleophilic substitution reactions can be defined as reactions in which one nucleophile replaces another attached to a saturated carbon atom. A SN2 reaction occurs as a one step process also referred to as a second order due to its rate and is favored by 1°. For these reactions the intermediate is called pentavalent carbon because although there should never be more than four bonds on carbon, the nucleophile attacks as the same time the leaving group makes its way out causing the intermediate to have a broken bond with the leaving group while it forms a bond with the nucleophile. This is a bimolecular reaction, making the rate of a SN2 reaction dependent on the concentration of both the nucleophile and the substrate. The NaI acetone is a polar

Read More
1046 Words | 5 Pages

ABSTRACT: The purpose of the experiments for week 5 and week 6 support each other in the further understanding of enzyme reactions. During week 5, the effects of a substrate and enzyme concentration on enzyme reaction rate was observed. Week 6, the effects of temperature and inhibitor on a reaction rate were monitored. For testing the effects of concentrations, we needed to use the table that was used in week 3, Cells.

Read More
1123 Words | 5 Pages

In addition, the number of cross-linking reactions may be take place, mainly depends on the reaction conditions such as temperature, catalysts, the structure of the alcohols, amines and isocyanates. Commonly used some isocyanates structures are shown in figure 1.2 that is toluenediisocyanate (TDI),

Read More
1408 Words | 6 Pages

3.1 Preliminary optimization studies 3.1.1. Effect of reaction time: Figure.3 represents the time progression for the enzymatic esterification of ethanol and hexanoic acid with 1:1 substrate ratio by Novozyme 435 (2 %) at 50 ˚C. It was observed that percentage conversion of ethyl hexanoate reached up to 73.6% in the initial 120 min. However, as the reaction proceeds further, a marginal change in conversion was observed after 120 min because of equilibrium of the reaction. This is attributed to the reversible nature of the esterification reaction. The slow rate of reaction after initial hours is due to collection over time of the reaction product on the enzyme this way reducing the surface area available for the reaction.

Read More
859 Words | 4 Pages

It is a more often observed biotransformation pathway for small endogenous compounds, but also plays a role in the metabolism of macromolecules like nucleic acids. Compounds can undergo N-, O-, S- and arsenic methylation catalyzed by enzymes called methyltransferases, employing S-adenosylmethionine as the methyl donor.95,98 Amino acid conjugation reactions are a route of metabolism of xenobiotic carboxylic acids. The enzymes of conjugation reside in mitochondria. Mechanistically, it differs from the other conjugation reactions. It involves initial activation of the carboxylic acid moiety with ATP, generating an acyl adenylate and pyrophosphate.

Read More

More about Comparing Two Types Of Nucleophilic Na

Related Topics

Open Document