> Which Of
> Which Of The Following Cannot Form An Enolate Anion
Which Of The Following Cannot Form An Enolate Anion
A crossed-aldol reaction simply implies that two different components were used, one to act as the nucleophile (electron donor) and one as the carbonyl (electron acceptor). A) A Ans: B B) B C) C D) D 8. Consequently, the resonance energy is relatively large. III d. http://dirsubmit.net/which-of/which-of-the-following-cannot-form-from-mesoderm.html
What is the relationship between the following two structures? Ans: D B) -ketoester. Since the carbonyl group of the carbonyl form is strongly electrophilic and reacts with a variety of nucleophiles, it would be reasonable to expect the strongly nucleophilic enolate to be able A) CH3CO2H and CH3CH2OH with H2SO4 as a catalyst B) CH3CO2H and CH3CH2OH with NaOH C) CH3COCl and CH3CH2OH with pyridine D) (CH3CO)2O and CH3CH2OH with H2SO4 as a catalyst Ans:
However, in the context of an intramolecular reaction in which the negative charge is in the same molecule as the hydroxyl group, it often occurs. Reaction of acetic acid, CH3CO2H, with isotopically labeled CH318OH and catalytic sulfuric acid gives: A) A Ans: B B) B C) C D) D Page 290 Chapter 18 Carboxylic Acids 17. What is the name of the following ester? A) FCH2CO2H B) ClCH2CO2H C) BrCH2CO2H Ans: A D) ICH2CO2H 10.
a. In contrast, most beta eliminations are concerted. Details of the Mechanism of Acid Catalyzed Bromination of Carbonyl Compounds. B) B C C) C D) D Page 341 D.
Sign up to view the full document. The rate of enol formation is exactly equal to the rate of formation of the brominated product. Which one of the following esters cannot form an enolate ion? Only then is the carbonyl component added.
Ans: B Page 287 Chapter 18 Carboxylic Acids 8. Acidity of Carbonyl Compounds. Also, we have seen that the enol contains an electron-rich alkene functionality, which should be highly reactive toward electrophiles. Strictly speaking, to be an enol the -OH and the C=C must be directly attached to one another, i.e., in conjugation with each other, as shown below.
two c. These are: (1) the enolate role and (2) the carbonyl role. Rank the following three carboxylic acids in order of increasing acidity. I.
In fact the K value is ca. 106 (remember how to calculate K's from the Ka's of the reactant and product acids?). The conjugate base of this substrate is highly resonance stabilized, having three relatively good resonance structures (recall that a ketone enolate only has two). Answer Questions If 22g copper sulfate are dissolved in100g water at 20 degrees C is solution saturated , unsaturated , supersaturated? Which of the following is the aldol addition product of butanal?
View Full Document This preview has intentionally blurred sections. You can only upload files of type PNG, JPG, or JPEG. How many -hydrogens does 2-hexanone have? have a peek at these guys benzaldehyde, C6H5CHO II. 2,2-dimethylpropanal, (CH3)3CCHO III. 2-chloropropanal, CH3CHClCHO A) only I B) only II C) only III Ans: C D) all of them have an enol form 4.
Note that the equilibrium lies on the side of the weaker acid (the carbonyl compound; water being the stronger acid), but the K value is ca. 10-3.
CO2Et CO2Et 1. A) A Ans: C B) B C) C D) D Page 308 Chapter 19 Carboxylic Acid Derivatives - Nucleophilic Acyl Substitution 25. As such it is especially highly acidic, so that the equilibrium goes to completion. a. 3 b. 4 *c. 5 d. 6 2.
A) resonance forms B) stereoisomers C) constitutional isomers D) different conformations of the same compound Ans: C 11. A *b. Relative Stabilities of the Carbonyl and Enol Isomers In a typical carbonyl/enol equilibrium, the equilibrium constant is about 10-5 , i.e., there is only about .001% of the enol. check my blog B) Acyl chlorides have a leaving group, Cl¯, whereas aldehydes do not.
Course Hero is not sponsored or endorsed by any college or university. In many cases it is possible to perform crossed aldol reactions between one of these non-enolizable carbonyl compounds and a general aldehyde. A) butanal Ans: B B) butyl acetate C) 2-hexanone Page 313 D) ethyl butanoate Chapter 19 Carboxylic Acid Derivatives - Nucleophilic Acyl Substitution 34. How many different Claisen condensation products are possible in the reaction of equal amounts of ethyl acetate (CH3CO2Et) and ethyl propanoate (CH3CH2CO2Et)?
It is the enol, not the carbonyl compound, which is reactive toward bromine. The pK's are typically about 19-20. only I B. Ans: A 32.