CHEM2314 Lab 3

The rate law for the reaction of HO- with tert-butyl bromide to form an elimination product in 75% ethanol/ 25% water at 30 °C is the sum of the rate laws for the E2 and E1 reactions. What percentage of the reaction takes place by an E2 pathway when [HO-] = 5.0 M? (k2 = 7.1 x 10-5, and k1 = 1.5 x 10-5)

Below is the equation for a nucleophilic substitution reaction and some experimental data. CH3CH2Br + CH3COO- ⇌ CH3CH2CO2CH3 + Br- Rate = k [CH3CH2Br][CH3COO-] Which mechanism would best fit the data?

i,ii,iv please

Treatment of 1,2-dibromoethane with the dithiolate dianion shown in the reaction below leads to two products as shown. Draw the structure for each molecular formula and provide a detailed mechanism for the formation of both products.

The sodium iodide test is used to identify primary alkyl halides and it also takes place via a substitution reaction.Describe the test including the reactions that explain the full mechanism. Explain whether this reaction follows aSN1 or a SN2 mechanism.

Why do cis-1-bromo-2-ethylcyclohexane and trans-1-bromo-2-ethylcyclohexane form different major products when they undergo an E2 reaction?

Treatment of 1,2-dibromoethane with the dithiolate dianion shown in the reaction below leads to two products as shown. Draw the structure for each molecular formula and provide a detailed mechanism for the formation of both products. CH,Br CH,SNa C4H8S2 + C,H12S,Br, CH,Br CH2SNa

Q10. For each of the following reactions (a-b), predict whether the substitution is more likely to occur following an Sn1 or Sn2 mechanism; explain your reasoning. Draw the products of each nucleophilic substitution paying particular attention to the stereochemistry of carbon 1. а) Br CH3 MeOH H3C b) Br NaOH DMF* H3C *N,N-dimethylformamide

I'm having trouble understanding what's wrong with this mechanism I've drawn. Can you assist me in identifying the errors in the drawing? Thank you.   Original Question: Propose a mechanism to show how 3,3-dimethylbut-1-ene reacts with dilute aqueous H2SO4H2SO4 to give 2,3-dimethylbutan-2-ol.

a) The radical chlorination of pentane is a poor way to prepare 1-chloropentane but radicalchlorination of neopentane, (CH3)4C, is a good way to prepare neopentyl chloride,(CH3)3CCH2Cl. Explain.b) Show the mechanism for the radical chlorination of neopentane. Illustrate homolytic bondcleavage and bond formation.

Through what basic mechanism is 1-methylcyclohexanol converted to 1-bromo-1- methylcyclohexane upon treatment with HBr? E2 E1 SN1 SN2 radical chain

The Wolff–Kishner reaction uses hydrazine (H2NNH2) and hydroxide (–OH) to reduce a carbonyl to the alkane. The first steps of the mechanism convert a carbonyl to a hydrazone in a manner similar to imine formation. Draw the mechanism arrows for the reaction from the hydrazone to the alkane. Be sure to add lone pairs of electrons and nonzero formal charges to all species.

Write out all the steps in the mechanism of this electrophilic aromatic substitution reaction. Include all resonance contributors. Benzene Cl₂ FeCl3 chlorobenzene

Consider the E1 reaction of 3-bromo-2-cyclohexyl-butane.  How many elimination products are possible?  Include (E)/(Z) isomers as separate products.

b).. .. Under each potential product of this E2 elimination, write "major product," "minor product," or "not formed." Me Br H Me Me OH Me Ph Ph H Me H Et Me Me Me Ph Ph Me Me Et

The rate constants for the bromination of several disubstituted stilbenes are given in the table below. Given that the double bond of stilbene acts as the nucleophile, provide a reasonable explanation for the trend observed among the rate constants. X -OMe -OMe -OMe -OMe oooo Br2 121 Y -OMe Me -Cl -NO₂ Br Br k(x103 1/mol-min) 220 114 45 5.2

3-Bromocyclohexene is a secondary halide, and benzyl bromide is a primary halide. Both halides undergo SN1 substitution about as fast as most tertiary halides. Use resonance structures to explain this enhanced reactivity.

OH NaOH H3C CH3 H3C CH3 Alkyl halides undergo nucleophilic substitution and elimination reactions. When the kinetics of the reaction are measured, if the rate of the reaction is found to be dependent only upon the concentration of the alkyl halide the reaction is first order. The substitution reaction is thus termed Sy1, and the elimination reaction is termed E1. These reactions are unimolecular and occur in two steps. The first step is rate-limiting and involves the loss of the leaving group to form a carbocation. In the second, fast, step the nucleophile adds to the carbocation in the SN1 reaction or elimination occurs to give an alkene in the E1 reaction. Because the carbocation is planar, the nucleophile can add to either face and therefore racemization is usually observed although solvent effects can influence this somewhat. E1 elimination follows Zaitsev's rule and typically yields the most substituted alkene as the major product. Conditions which favor the Sy1/E1 pathway include…

Br Brz CH3 CH3 H3C CH2CI2 H3C Br Electrophilic addition of bromine, Br2; to alkenes yields a 1,2-dibromoalkane. The reaction proceeds through a cyclic intermediate known as a bromonium ion. The reaction occurs in an anhydrous solvent such as CH,Cl). In the second step of the reaction, bromide is the nucleophile and attacks at one of the carbons of the bromonium ion to yield the product. Due to steric clashes, the bromide ion always attacks the carbon from the opposite face of the bromonium ion so that a product with anti stereochemistry is formed. Draw curved arrows to show the movement of electrons in this step of the mechanism. Arrow-pushing Instructions Br: :Br: .CH3 H3C H3C CH3 Br:

Can you explain the reasons and concepts for why this answer is true?

Complete the synthesis of ethyl (E)-2,2,4-trimethyl-3-oxo-5-phenylpent-4-enoate from the starting material given (ethyl propionate). You must list out all reagents/solvents next to the reaction arrows and draw the intermediate structures in the boxes. I am giving you one restriction. You are not allowed to introduce any enolates as reagents next to the reaction arrows.

Ff.144.