FA23 CHEM 225 Exp9 HANDOUT_E2 Rxn_001 (1)

Reaction of propene (above) with HBr might, in principle, lead to a mixture of two alkyl bromide addition products. Name these two alkyl bromides.

My Organic Chemistry textbook says about the formation of cyclic hemiacetals, "Such intramolecular reactions to form five- and six-membered rings are faster than the corresponding intermolecular reactions.  The two reacting functional groups, in this case OH and C=O, are held in close proximity, increasing the probability of reaction."According to the book, the formation of cyclic hemiacetals occurs in acidic conditions. So my question is whether the carbonyl group in this reaction reacts first with the end alcohol on the same molecule or with the ethylene glycol.  And, given the explanation in the book, if it reacts first with ethylene glycol before its own end alcohol, why would it?  I don't need to know the final answer.  I need to know WHY it would not undergo an intermolecular reaction prior to reacting with the ethylene glycol if that is the case.  Please do not use an AI answer.

Alkynes do not react directly with aqueous acid as do alkenes, but will do so in the presence of mercury(II) sulfate as a Lewis acid catalyst. The reaction occurs with Markovnikov regiochemistry, so the OH group adds to the more highly substituted carbon and the H adds to the less highly substituted carbon. The initial product of the reaction is a vinyl alcohol, also called an enol. The enol immediately rearranges to a more stable ketone via tautomerization. Draw curved arrows to show the movement of electrons in this step of the mechanism. Arrow-pushing Instructions -X티 Hö: H-O -CH3 -CH3 H30*

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…

[Review Topics] [References] HO pyridine 1. SOCIl, + sO2 + H. Aqueous acetone H3C H20 H3C HBr 2. Br H OH optically active racemic f = SN1 Nucleophilic substitution g = SN2 Nucleophilic substitution a = Proton transfer d = E1 Elimination b = Lewis acid/base e = E2 Elimination c = Electrophilic addition The rections above involve synthesis or reactions of alcohols and ethers. Identify the mechanism by which they proceed from among the mechanisms listed. Use the letters a - g for your answers. 1. 2.

Only one of the chlorine atoms in the molecule, 3,4-dichloronitrobenzene, will undergo nucleophilic substitution. Indicate which position will react and provide the expected product for the given reaction using reaction intermediates (resonance structures).

Functional groups such as alkynes react the same in complex molecules as they do in simpler structures. The following example  of alkyne reaction  were taken from syntheses carried out in the research group of E. J. Corey at Harvard University. You can assume that the reactions listed involve only the alkyne, not any of the functional groups present in the molecules. Draw the expected products for the following reaction .

1. You are planning to carry out a reaction between butyne CH3CH₂C=CH, and sodium methoxide, CH3ONa. You also need to choose an appropriate solvent for the reaction. Would H₂O be an appropriate solvent? Explain your rationale.

CH3 CH3 Br- Br2 .CH3 CH2Cl2 CH3 H3C H3C Br Electrophilic addition of bromine, Brɔ, 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 CH3 CH3 CH3 CH3 H3C H3C :Br: :Br:

Compare the two reactions shown below. excess LICH,CH3 excess LICH,CH3 Both electrophiles, an ester and a ketone, are reacted with an excess amount of LICH2CH2. Which reaction will result in the formation of a product with the molecular formula C9H200 and why? O A: Only the reaction with the ester. LICH2CH3 results in an addition mechanism with both starting materials. However, the product from the ketone reaction contains fewer than 9 carbons. O B. Only the reaction with the ketone. LICH2CH3 results in an addition mechanism with both starting materials. However, the product from the ester reaction contains two oxygen atoms. O C. Both reactions. LICH2CH3 results in an addition mechanism with the ketone. However, the ester goes through a SNAC mechanism because it contains a leaving group, which allows two equivalents of LICH2CH3 to attack. O D. Neither reaction. LICH2CH3 results in a SNAC mechanism with both starting materials. Both products contain more than 9 carbons.

i need help drawing the product

A lab technician planned to synthesize 2-bromopentane using 2-pentanol, heat, and HBr. However, the labtechnician did not have HBr in the lab. What other reagent(s) can the technician use to synthesize 2-bromopentane using 2-pentanol as the starting material?

4. Synthesize the following compound. You may use benzene, acetylene, ethanol and any inorganic reagents. O₂N

Acyl transfer (nucleophilic substitution at carbonyl) reactions proceed in two stages via a "tetrahedral intermediate." Draw the tetrahedral intermediate as it is first formed in the following reaction. CI H₂N OH • You do not have to consider stereochemistry. • Include all valence lone pairs in your answer. • Do not include counter-ions, e.g., Na+, I, in your answer. • In cases where there is more than one answer, just draw one. Sn [F

Select the reagent that you would use to convert an alkene to a Markovnikov (more substituted) alcohol without possibility of carbocation rearrangement. o H2SO4, H2O OBH3-THF, then H2O2, H2O, NaOH Hg(OAc)2, H2O, then NaBH4 o OsO4, TBHP, H2O

Acyl transfer (nucleophilic substitution at carbonyl) reactions proceed in two stages via a "tetrahedral intermediate." Draw the tetrahedral intermediate as it is first formed in the following reaction. CI + H₂N • You do not have to consider stereochemistry. • Include all valence lone pairs in your answer. OH • Do not include counter-ions, e.g., Na+, I¯, in your answer. • In cases where there is more than one answer, just draw one.

Consider the reaction below to answer the following questions. When dichlorocarbene is generated in the presence of an alkene, a dichlorocyclopropane is formed. Cl. CL CH₂ ( H₂C H C=C H + CHCl3 KOH H₂C--- CH3 H H Write the complete stepwise mechanism for the formation of dichlorocarbene, :CCl₂. Show all intermediate structures and show all electron flow with arrows.

Acyl transfer (nucleophilic substitution at carbonyl) reactions proceed in two stages via a "tetrahedral intermediate." Draw the tetrahedral intermediate as it is first formed in the following reaction. 0 OH CI + H₂N • You do not have to consider stereochemistry. • Include all valence lone pairs in your answer. • Do not include counter-ions, e.g., Na+, I, in your answer. In cases where there is more than one answer, just draw one. A ChemDoodle Activate Windows

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4. When analyzing a synthesis, it is extremely important to identify functional groups and the reactions that can make them. Fill in the following chart for the functional groups you learned to make this semester. Note that there may be more than one answer, and that X = Cl or Br here. Functional Group Starting Material = alkyne E-alkene (trans) Z-alkene (cis) Å epoxide X two anti halogens on adjacent carbons НО anti halohydrin OH alcohol, most substituted carbon OH alcohol, least substituted carbon halide, most substituted carbon .X halide, least substituted carbon Reagents

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4. Dissolvable sutures are often used in medicine and dentistry so that additional surgeries don't need to be done to remove the stitches. Two examples of dissolvable sutures are: fart CH2 -CH2 Dexon® and -CH2 -CH2 -CH2 CH, -CH2 PDS® Using the organic chemistry you have learned so far, propose a mechanism for how they dissolve.

3 9 $ 4 R H₂C B % 5 1. Aqueous ethanol HBr CH₁ 2. OH a Proton transfer d E1 Elimination. f = SN1 Nucleophilic substitution b Lewis acid/base. e E2 Elimination g= SN2 Nucleophilic substitution c = Electrophilic addition The rections above involve synthesis or reactions of alcohols and ethers. Identify the mechanism by which they proceed from among the mechanisms listed. Use the letters a- g for your answers. 1. 2. Submit Answer Retry Entire Group 9 more group attempts remaining Previous Next> Save and Exit Cengage Learning Cengage Technical Support O 8:15 AM 6/20/2022 PrtScn PgDn F5 F6 T B CH₂ Nà Nha ^ 6 Y H N & 7 [Review Topics] H₂C U 8 M CH₂ NH₂ K [References] H₂C 73°F Sunny Home ( 9 O L End 0 G F10 P PgUp 4x F12 □