All Practice Problems
Problem 286
Draw the conjugate base forms of each acid listed below, then rank the acids in order or decreasing acidity (1 = most acidic). Explain your...
Problem 288
Draw the conjugate base form of each acid listed below, then rank the acids in order or decreasing acidity (1 = most acidic). Explain your...
Problem 303
Draw the conjugate base form of each acid listed below, then rank the acids in order or decreasing acidity (1 = most acidic). Explain your...
Problem 304
Draw the conjugate base form of each acid listed below, then rank the acids in order or decreasing acidity (1 = most acidic). Explain your...
Problem 305
Rank each group of acids in order of decreasing acidity. (1 = most acidic) Explain your reasoning. You will have to use more than one rule in...
Problem 306
Rank each group of acids in order of decreasing acidity. (1 = most acidic) Explain your reasoning. You will have to use more than one rule in...
Problem 307
Rank the group of molecules below in in order of decreasing basicity. (1 = most basic) Explain your reasoning.
Problem 308
Rank the group of molecules below in in order of decreasing basicity. (1 = most basic) Explain your reasoning.
Problem 309
Convert each formula to a carbon skeleton diagram, or vice-versa.
Problem 310
For each molecule, determine the formal charge of the indicated atom.
Problem 311
For each molecule below, draw in all implied lone pairs and/or protons (hydrogens) based on the formal charge shown.
Problem 312
Draw all possible resonance forms for each structure below. Use curved arrows. Note that some structures only show charge, and not implied...
Problem 313
Draw all possible resonance forms for each structure below.Use curved arrows. Note that some structures only show charge, and not implied protons...
Problem 314
Draw all possible resonance forms for each structure below.Use curved arrows. Note that some structures only show charge, and not implied protons...
Problem 315
Draw all possible resonance forms for each structure below.Use curved arrows. Note that some structures only show charge, and not implied...
Problem 317
-D-Glucose is shown below. Draw its two chair forms. Which conformation is more stable? Explain. I recommend using the common convention wedge...
Problem 318
Two stereoisomers of trimethylcyclohexane are shown below (compounds A and B). Compare cyclohexane chair forms to determine which isomer has a...
Problem 319
For a molecule to undergo an E2 reaction, the leaving group and the beta-proton must be in an anti-coplanar conformation (one atom straight up...
Problem 320
Lets perform conformational analysis on 2-methylbutane along the C2-C3 bond. Well use the energy chart given below. First, draw out the...
Problem 321
Using curved arrows, draw a mechanism for the SN1 reaction shown below.
Problem 322
Using curved arrows, draw a mechanism for the SN1 reaction shown below.
Problem 324
Using curved hooks, draw a mechanism for the free radical bromination reaction shown below.
Problem 331
Rank the carbocations below in order of decreasing stability. (1 = most stable)
Problem 332
Each of the carbocations below will spontaneously rearrange. Draw the structure of the expected rearrangement product.
Problem 333
Lets go over how a carbocation can form from an alcohol. Write in the curved arrows to show the formation of the protonated alcohol, and water...
Problem 334
Lets go over how a carbocation can form from an alkene. Use curved arrows to show the two carbocations that can from from 1-methylcyclohexene.
Problem 335
Carbocations arent very stable and so dont last very long after they are formed. Use curved arrows to show: a) how a carbocation reacts with a...
Problem 336
Predict the product(s) of the reaction below, and used curved arrows to show a mechanism.
Problem 337
Predict the product(s) of the reaction below, and used curved arrows to show a mechanism.
Problem 341
Predict the product(s) of the reaction below, and used curved arrows to show a mechanism.
Problem 342
For the reaction below, draw the structures of the carbocation intermediate and thefinal product.
Problem 343
For the reaction below, draw the structures of the chloronium ion intermediate and thefinal product.
Problem 344
For the reaction below, draw the structures of the borane intermediate and thefinal product.
Problem 345
For the reactionbelow, draw the structures of the radical intermediate and thefinal product.
Problem 346
For the reactionbelow, draw the structures of the radical intermediate and thefinal product.
Problem 347
For the reactionbelow, draw the structures of the carbocation intermediate and thefinal product.
Problem 348
For the reactionbelow, draw the structures of the carbocation intermediate and thefinal product.
Problem 518
The alcohol below is protonated and contains an oxygen with a positive charge. Using curved arrows, show the two legal moves that result in a...
Problem 519
Lets work through an elimination reaction. Draw the structures for each of the species in the three boxes below (protonated thiol, carbocation...
Problem 520
Lets work through an alkene addition reaction.Draw the structures for each of the species in the three boxes below (3carbocation, protonated...
Problem 521
Lets work through a halogenation reaction. Draw the structures for each of the species in the four boxes below (3 carbocation, halonium ion...
Problem 522
Lets work through a 1,2 and 1,4 addition. Draw the structures for each of the species in the six boxes below. Also draw curved arrows to show...
Problem 525
On the molecule below, mark each stereocenter with an asterisk. (Note: in some textbooks, stereocenters are referred to as stereogenic centers...
Problem 526
Assign R or S configuration for each molecule below. a) is straightforward. Ive started you off in b).
Problem 527
Draw the structure of (2R,3S) 2-bromo-3-chlorobutane using wedges and dashes. Also draw a Fischer projection.
Problem 528
Indicate which of the molecules below are chiral (if any).
Problem 529
Indicate the major organic product of the reaction below. Include stereochemistry.
Problem 530
Lets work through anti and syn additions to alkenes. Show the product for each reaction below, and indicate whether the product will be a...
Problem 531
E2 elimination reactions require anti-coplanar geometry. (note: some textbooks call this anti-periplanar). Lets work through an E2...
Problem 532
Lets work through a chiral resolution. Write out the structure of the indicated compound in each box. Include stereochemistry. Why is it possible...
Problem 534
Using curved arrows, draw the mechanism for the SN2 reaction below.
Problem 535
Rank the following anions in order of decreasing stability (1 = most stable)
Problem 536
Rank the following electrophiles in order of decreasing reactivity with NaN3 in DMF.(1 = most reactive)
Problem 537
Indicate the reagents necessary to carry out each transformation.
Problem 538
Rank the following electrophiles in order of decreasing reactivity with NaN3 in DMF. (1 = most reactive)
Problem 539
Rank the following compounds in order of decreasing nucleophilicity. (1 = most nucleophilic)
Problem 540
Rank the following anions in order of decreasing stability (1 = most stable)
Problem 541
Rank the following compounds in order of decreasing reactivity with NaI in acetone. (1 = most reactive)
Problem 542
Rank the following compounds in order of decreasing reactivity with water (solvolysis). (1 = most reactive)
Problem 560
For each reaction below, determine whether the primary reaction is SN1, SN2, E1, or E2, and then draw the product. Note: Me = methyl (CH3)
Problem 561
Fill in the product for each reaction below. Indicate stereochemistry where appropriate.
Problem 562
Fill in the product for each reaction below. Indicate stereochemistry where appropriate.
Problem 569
Draw all resonance forms for each species. For the anion and cation species, used curved arrows. For the radical species, use hooks.
Problem 570
Rank the following dienes in order of decreasing reactivity with a dienophile in a Diels-Alder reaction. (1 = most reactive).
Problem 571
Write the structure of the major organic product of each reaction.
Problem 572
Lets work through a conjugate addition problem. Write out the mechnanism for the formation of the 1,2 and 1,4 products of the reaction below.
Problem 574
Predict the product for each Diels-Alder reaction. Indicate stereochemistry where appropriate.
Problem 575
Predict the product for each Diels-Alder reaction. Indicate stereochemistry where appropriate.
Problem 576
Retro Diels-Alder: show a combination of diene and dienophile that would result in each Diels-Alder adduct.
Problem 577
Retro Diels-Alder: show a combination of diene and dienophile that would result in each Diels-Alder adduct.
Problem 580
Draw all resonance forms for each species. For the anion and cation species, used curved arrows. For the radical species, use hooks.
Problem 581
Draw all products for the two reactions below. The allylic alkene gives two products- the 1,2 product, and the 1,4 product. However, the...
Problem 582
Rationalize the follwing pKa values. Explain your answer in terms of the stabilites of the conjugates bases of each acid. Note: the lower the...
Problem 583
Pyrrole is an example of a heteroaromatic compound: it contains a heteroatom (atom that is not carbon or hydrogen, such as N, O, S, etc.), and is...
Problem 584
Imidazole (shown below) has two nitrogen atoms, N-1 and N-3.Which nitrogen is more basic? To answer this problem, draw the product after each...
Problem 587
Use curved arrows to draw a mechanism for the generic electrophilic aromatic substitution (EAS) reaction below.
Problem 588
Lets draw resonance forms to see why some groups are EDG or EWG. (Ive started you off) Where are the positive or negative charges placed in...
Problem 589
-OR is an EDG and an ortho-para director. Lets draw an EAS reactions cyclohexadienyl cation intermediates to demonstrate why this is true. Ive...
Problem 590
-NO2 is an EWG and a meta director. Lets draw an EAS reactions cyclohexadienyl cation intermediates to demonstrate why this is true. Ive started...
Problem 591
Pyrrole undergoes eletrophilic aromatic substitution at C-2. Lets compare the resonance forms of EAS carbocation intermediates to see why this is...
Problem 592
Naphthalene undergoes eletrophilic substitution at C-1. Why is this the case, even though substitution at C-2 gives more resonance forms?
Problem 593
a)Rationalize the relative stabilities of the cation species below. b) Pyridine undergoes eletrophilic substitution at C-3. Lets compare the...
Problem 594
A chemist tried to prepare compound A from benzene via Friedel-Crafts alkylation and instead produced compound B. Why did this happen? How could...
Problem 595
Phenol can be prepared from benzene and hydrogen peroxide in the presence of a really strong acid. Propose a mechanism for this reaction.
Problem 596
Indicate the eletrophile formed by each set of reagents/conditions below.
Problem 611
Draw in the arrows to show the electron flow and resonance forms in the nucleophilic aromatic substitutionreaction below. Note: Depending on the...
Problem 612
Draw a mechanism for the nucleophilic aromatic substitution (SNAr)reaction below. Show all resonance forms of the intermediate.
Problem 615
Lets go through a benzyne reaction (also called elimination-addition). In the reaction below, the strong base (NaNH2) will form a benzyne...
Problem 616
Lets go through another way to make benzyne. First, lets form a Grignard reagent. Then, lets elminate to form benzyne.
Problem 657
The mass spec of chlorocyclohexane shows a peak at m/z = 83. Use curved arrows to show the heterolytic cleavage that accounts for this fragment.
Problem 658
The mass spec of methyl ethyl ether shows peaks at m/z = 45 and 59. Use hooks to show the alpha cleavages that result in these two fragments.
Problem 659
The mass spec of 4-nonanone shows peaks at m/z =58, 71, 86, 99. Using curved arrows or hooks, show how each of these fragments can form via...
Problem 660
Using your knowledge of 1H NMR, predict the NMR spectrum for the compound below. (draw out the spectrum you would expect to see).Be sure to...
Problem 661
The proton NMR of cyclohexane gives only one peak when the NMR is run at room temperature. But when the temperature is lowered to -100 C the...
Problem 662
The 1H and 13C NMR spectra of a compound with chemical formula C10H14O are shown below. The compounds IR spectrum shows a broad peak at 3,300...
Problem 663
The 1H and 13C NMR spectra of a compound with chemical formula C4H6O2 are shown below. The compounds IR spectrum shows a sharp peak at 1,700 cm-1....
Problem 665
The 1H and 13C NMR spectra of an unknown compound are shown below. The compounds mass spectrum shows a molecular ion with m/z ratio of 86....
Problem 666
The 1H and 13C NMR spectra of an unknown compound are shown below. The compounds mass spectrum shows a molecular ion with m/z ratio of 122....
Problem 668
Show how each alcohol can be prepared from a combination of a carbonyl and a Grignard reagent.
Problem 669
In your own words, what is the major difference in the addition of a Grignard reagent to an oxidation state III carbonyl (ester/acid chloride)...
Problem 670
Draw out the mechanism for the addition of excess phenyl Grignard to the carbonyl compound below.
Problem 671
You may have noticed that the solvent of choice for many organometallic compounds such as Grignard reagents is ether (short for diethyl...
Problem 672
Compound A has molecular formula C6H12O and shows a sharp peak at 1,710 cm-1 in its IR spectrum. Treatment with 1 equivalent of phenyl Grignard...
Problem 673
Show how each compound can be prepared from an alkene containing 3 carbons (or less). Each answer will involve the reaction of a Grignard with...
Problem 674
Show a mechanism for the reduction of butyrolactone using LiAlH4.
Problem 677
Show a mechanism for the acid-catalyzed cyclization (condensation) of 1,4-butanediol.
Problem 678
Draw the structure of the major organic product from each reaction sequence.
Problem 679
Compound A (C5H12O) is oxidized using aqueous chromium (Jones reagent) to compound B (C5H10O2), which is then treated with methanol under acidic...
Problem 697
Rank the following compounds in order of decreasing boiling point. Also, make a guess about their relative solubilities in water. Explain your...
Problem 698
When propyl bromine is treated with KF in benzene no reaction takes place. But when the crown ether 18-Crown-6 is added to the reaction mixture...
Problem 699
Show how each compound can be prepared from the indicated starting material. All carbon sources must contain three carbons or less.
Problem 700
Write out a mechanism for the reaction below using curved arrows. Be sure to include formal charges.
Problem 701
The acid-catalyzed condensation of alcohols to form ethers is reversable; ethers can be hydrolyzed back to alcohols. How can the direction of this...
Problem 702
Show how to prepare each compound starting from propylene oxide. (Propylene oxideimage below courtesy of Wikipedia.)
Problem 703
Show two ways to prepare the ether below from a combination of an alcohol and an alkyl halide via the Williamson ether synthesis. Is one way...
Problem 705
Carbonyls are in equilibrium with their hydrate forms. This equilibrium happens in both acid and base. Lets go through this equilibrium under...
Problem 706
Carbonyls are in equilibrium with their hydrate forms.This equilibrium happens in both acid and base. Lets go through this equilibrium under...
Problem 707
The overall mechanism for imine formation is shown below. (This isnt a real mechanism, just an outline) Use curved arrows to draw the full...
Problem 708
The overall mechanism for Fischer esterification is shown below. This isnt a real mechanism, just an outline. Methanol (the nucleophile) attacks...
Problem 710
Rank the carbonyls A-D below in order of decreasing electrophilicity (reactivity with nucleophiles). (1 = Most reactive). Explain your reasoning.
Problem 711
Show two ways of preparing the alkene below via the Wittig reaction starting from triphenyl phosphine (PPh3). Is one route better than the other?...
Problem 712
Show what combination of amine and carbonyl would result in each imine or enamine.
Problem 713
When a carbonyl is treated with semicarbazide under acidic conditions an imine is produced called a semicarbazone. Which of the two products...
Problem 714
Complete each synthesis below. All carbon sources must come from alkenes. Each synthesis will involve protecting groups.
Problem 715
-D-glucose is shown below. a) Is -D-glucose an acetal, hemiacetal, ketal, or hemiketal? b) Draw the carbonyl form of -D-glucose.
Problem 717
Rank each of the eight compounds A through H below in order of decreasing acidity (1 = most acidic). Dont get intimidated! What are the...
Problem 720
Base your answers to the three problems below on your knowledge of electron donating groups and electron withdrawing groups (EDG and...
Problem 721
Rank each of the four compounds below in order of decreasing acidity (1 = most acidic).
Problem 722
Show how to prepare vinyl benzene from benzene.
Problem 723
Show how to prepare each compound from vinyl benzene. How would you prepare the methyl ester of each compound?
Problem 724
Use curved arrows to show the formation of the tetrahedral intermediate of a Fischer esterification reaction (shown below). There are three steps...
Problem 725
A chemist carried out a Fischer esterification using methanol that was isotopically labeled with 18O (indicated with an asterisk). Which one of...
Problem 726
Show two esters that would yield the two alcohols below after treatment with lithium aluminum hydride.
Problem 727
Show how the ester below can be prepared from propene.
Problem 728
The acyl group is a protecting group for amines. Amines can be acylated using acetic anhydride, and deacylated with base. Propose a mechanism for...
Problem 729
The ester below was dissolved in a solution of water, a small amount of which was isotopically labeled with O-18, denoted with an asterisk. After...
Problem 730
N,N-dimethylformamide (DMF) is shown below. Based on its structure, you might expect to see only one -CH3 signal in the 1H NMR spectrum. But...
Problem 735
Show how each ketone below can be prepared from sodium cyanide and either ethylene or propene. You may also use methyl Grignard and ethylene...
Problem 738
Carbonyls are in equilibrium with their enol forms. This process is called keto-enol tautomerization. This equilibrium happens in both acid and...
Problem 739
Carbonyls are in equilibrium with their enol forms. An enolate is the deprotonated form of an enol. Enolates are formed from carbonyls under...
Problem 740
Enolates are formed from carbonyls by adding a strong base, such as lithium diisopropyl amide (LDA), to deprotonate the alpha position. The...
Problem 741
Like enolates (Q740), enols can also act as nucleophiles and make new bonds at the alpha position. Lets go through the mechanism for how this...
Problem 742
Enamines are similar to enols and enolates in that they also undergo alpha substitution reactions. The process of performing a carbonyl alpha...
Problem 743
Enolates are nucleophiles and react with a variety of electrophiles. Carbonyls are electrophiles. But aldehydes/ketones and esters/acid chlorides...
Problem 744
After a sample of optically pure (S)-2-ethyl-cyclohexanone is dissolved in an aqueous solution for several hours, a significant loss of optical...
Problem 745
The molecule below has five different types of hydrogens (A throughE). Rank each in order of decreasing acidity. (1 = most acidic). Explain your...
Problem 746
Show what combination of aldehyde, ketone, and/or ester can prepare each compound below. Every compound is a Claisen or aldol product.
Problem 747
Show a combination of enolate (nucleophile) and electrophile that can produce each compound below. Remember that all enolates come from...
Problem 748
Alpha bromination is usually carried out under acidic conditions via the enol intermediate. Alpha bromination is uncontrollable under basic...
Problem 749
Show how to prepare each compound below from propanal. Ive marked the cuts for you.
Problem 750
Lets work through a Robinson annulation. Work backwords to determine the starting materials needed to produce each intermediate below, then show...
Problem 752
Rank the amines A through D below in order of decreasing basicity (1 = most basic). Explain your reasoning.
Problem 753
Rank the amines W through Z below in order of decreasing basicity (1 = most basic). Explain your reasoning.
Problem 754
Show how each amine can be prepared from a carbonyl and an amine via reductive amination.
Problem 755
The nitrosyl cation is shown below. Also shown are several proposed resonance arrows, only one of which is correct. Draw the resonance forms that...
Problem 756
For each amine below, show all Hofmann elmination products. If more than one product is formed, predict which one will be the major product.
Problem 757
Propose a synthesis to accomplish each transformation. The only carbon sources allowed are alkenes and NaCN.
Problem 1280
The structure of 2-methylbutane is shown below. a) Draw the structures of all possible monochloro products resulting from the free-radical...
Problem 1281
Allylic and benzylic halides tend to undergo both SN1 and SN2 substitution reactions at a faster rate than their alkyl counterparts. For example...
Problem 1286
For the molecule shown below, indicate the hybridization (sp3, sp2, sp, etc.)of atoms A through H, and the bond angles of X, Y, and Z.
Problem 1287
Rank each set of compounds in order of decreasing boiling point (1 = highest boiling point): a) ethane, n-octane, n-pentane b) n-butane...
Problem 1336
Determine a synthesis to prepare 2-chloro-4-methylpentane from 1-iodo-4-methylpentane. from
