HW 9

4) When a mixture of two different compounds both containing a hydrogens are placed under acidic or basic conditions, crossed aldol products can be formed. By either self-condensation or cross condensations. Draw the 4 aldol and 4 a.B-unsaturated ketones that can be made from the following mixed system. -OH 4 products One way to control this is by either having only one compound with a hydrogens or by reacting the desired nucleophile with lithium diisopropylamide (LDA) before addition of second carbonyl. The issue here is that this reaction stops at the aldol unless excess base is used. он LDA OH heat Show a synthetic scheme of how to use the following carbonyls to control the formation of each cross product (i.e. each as nucleophile and electrophile, two reactions). and

1. Discuss the role of the Aldol condensation reaction in the synthesis below. What specific reaction was used in the synthesis? What is the importance of the aldol reaction in the entire synthetic approach? 2. Show the detailed reaction mechanism involved in their corresponding specific parts in this syntheses.

1. Give the synthetic route.

What types of species are the electrophile and nucleophile in an aldol addition? 1. Nu: ester, E+: carbonyl 2. Nu: carbonyl, E+: carbonyl 3. Nu: carbonyl, E+: ester 4. Nu: ester, E+: ester

Using the diagram below, answer the ff. questions.1. What pattern of curved arrow pushing is the second step of this reaction?a. loss of a leaving groupb. proton transferc. rearrangement 2. What pattern of curved arrow pushing is the fourth step of this reaction?a. proton transferb. loss of a leaving groupc. nucleophilic attack

1. Williamson Ether Synthesis Questions for lab , Synthesize phenacetin from acetaminophen (Tylenol) via a Williamson ether synthesis.   a.Find the missing reagent:CH3CH2OH +? → C2H5OC2H5     H2SO4,      H2O     HNO3,     H2CO3     b.What is the nucleophile in this reaction?     H2O     Nu-     RO-     ROH c.If you wanted to prepare Guaifenesin (present in OTC cough meds), choose the alcohol you would start with?     2 methoxy benzoinc acid     2-methoxy benzaldehyde     2-methoxyphenol     2 methoxy anisole d.What was the mechanism of the reaction you used to prepare the ether?     SN1     SN2     E1     E2 e.The reaction given below is known as by which o the following reaction? C2H5ONa+IC2H5→C2H5OC2H5+NaI     Oxidation reaction     Williamson reduction reaction     Williamson ether synthesis     Wittig synthesis f.Chloroethane reacts with X to form diethyl ether. What is X?…

What is the first step in a base catalyzed aldol reaction?   A. Protonation of Carbonyl group   B. Elimination of Carbonyl with an alkene   C. Formation of an Enolate   D. Elimination of hydroxide   E. Addition of nucleophile to R2C=O

6. Multi Step Synthesis. Propose a synthetic route from the reactant to the product using any reagents you need. Nalt LINH4

How does gold help to catalyze the reaction in the gold catalysis experiment? It deprotonates the methanol, making methanol a better nucleophile. оа. o b. It donates electron density to the alkyne, making the alkyne a better nucleophile. О с. It coordinates to the methanol, making methanol a better nucleophile. o d. It coordinates to the alkyne, making the alkyne a better electrophile.

2. When the following pair of reactants are combined in the presence of a basic catalyst, a number of aldol addition products are possible). NaOH/H₂O A CH3 a. b. C. H₂C Draw the structure for the enolate ion (show both of the relevant resonance structures). Draw the structures for all possible aldol addition products (also show the enolate ion and electrophilic carbonyl compound responsible for each product). For each of the aldol addition products predicted in part b, draw the structures for all of the corresponding aldol condensation products after loss of water (if E/Z isomers are possible, show both isomers)

6. The synthesis of alpha enol derivatives is important since these compounds with appropriate substituents in the correct positions can have desired biological effects, which is why the study of obtaining these compounds is important. Thus, a reaction from alpha-ketones with a lithium derivative is studied. a. Indicate the reaction intermediate and product. b. Perform the reaction mechanism. Eter H20 Intermediate Product

Please, I need help with the question below. I will rate it  Explain which mechanism is predominant in each of the above elimination reactionsand how it affects the product formation.  Thank you for your help.

1. For the following reaction step, indicate which pattern of arrow pushing it represents. a. proton transferb. rearrangementc. loss of a leaving group2. Melphalan, a drug used in chemotherapy, reacts with itself in the body before binding with its target, as illustrated in the mechanism below. What is the first pattern of arrow pushing seen in this reaction? a. rearrangementb. loss of a leaving groupc. nucleophilic attack

Draw the major product of this aldol addition reaction. Ignore inorganic byproducts.

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3. Draw all products for the following reactions. For your products, write whether the nucleophile added to the Re face or Si face of the starting material. a. HO b. 1) LIAIH 2) H™ 1) CH3CH2Li 2) H+ c) Determine whether the nucleophile added to the Re face or Si face of benzaldehyde.

10. Explain the reaction shown below. Include the following pieces in your explanation. Identify the electrophile and the nucleophile. Draw a curved arrow mechanism for this reaction. (Assume an acidic work-up). Explain the electron flow. Indicate any regiochemical or stereochemical preferences. one b. c. d. LIAIH4 OH one

6. The structures of two molecules, a B-keto ester and a B-unsaturated ketone, are given below. Retrosynthetically thinking, please draw the starting materials needed to make each of these molecules via a Mixed Claisen reaction and a Mixed Aldol reaction, respectively. Mіxed Mіxed Claisen Aldol

8. Using the Enamines as nucleophiles, draw the final product. N-H H*

Identify the stronger nucleophile in each pair of anions. a.Br− or Cl− in a polar protic solvent b.HO− or Cl− in a polar aprotic solvent c.HS− or F− in a polar protic solvent

help me please

1. As we've seen, SN1/El reactions can be quite messy and can generate multiple products. Consider the reaction shown in order to answer questions a-c. a. Draw the carbocation intermediate that is formed during the SN1/E1 reaction in Box 1. Вох 1 Br ELOH Carbocation b. Draw ALL possible elimination and substitution products that can be formed from the carbocation you drew in part a, and label the most and least stable alkene products. (Hint: There are 5 possible products.) Elimination Substitution c. Now, draw the arrow-pushing mechanism for the El reaction that forms most stable alkene product. 'Br EŁOH

a. Propose a mechanism for the following reaction.b. Explain why two products are formed.c. Explain why methanol substitutes for only one of the bromines.

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Hi, it's just one question but 3 subparts, and you are only allowed to answer up to 3 sub-parts please show the work clearly for all. Thank You