Your task is to prepare isopropyl methyl ether by one of the following reactions. Which reaction would give the better yield? Explain your answer. (1) Isopropyl methyl ether Or (2) Isopropyl methyl...
Predict the more stable alkene of each pair: (a) 2-methyl-2-pentene or 2,3-dimethyl- 2-butene; (b) Cis-3-hexene or trans-3-hexene; (c) 1-hexene or cis-3-hexene; (d) Trans-2- hexene or...
Sketch the 1H NMR spectrum you would expect for the following compound, showing the splitting patterns and relative position of each signal. CI CI Cl CI CI CI
Predict the product of the following reaction. O (1) BrMg (2) H2O MgBr (1 equiv.)
Provide the reagents needed to accomplish transformations (a)-(g). More than one step may be necessary. OH OH OH OH OMe
Synthesize the following compound using cyclopentane and ethyne (acetylene) as the sole source of carbon atoms.
Outline all steps in a synthesis that would transform 2-propanol (isopropyl alcohol) into each of the following: (a) (b) (c) (d) (e) CI
Draw transition states for the endo and exo Diels-Alder reaction of maleic anhydride with cyclopentadiene. The transition state leading to only one enantiomer need be shown in each case.
UV-Vis, IR, NMR, and mass spectrometry are spectroscopic tools we use to obtain structural information about compounds. For each pair of compounds below, describe at least one aspect from each of two...
From each set of resonance structures that follow, designate the one that would contribute most to the hybrid and explain your choice: (a) (b) (c) (d) (e) (f) HO HO
Predict the products of the following reactions. (a) (b) (c) (d) (e) (f) (g) (h) CN A OMe O+ OMe A (2) NaBHs (3) H2O OMe MeO 0 CN CN
(a) In 1960 T. Katz (Columbia University) showed that cyclooctatetraene adds two electrons when treated with potassium metal and forms a stable, planar dianion, C8H82- (as the dipotassium salt): Use...
Consider these reactions: The intermediate A is a covalently bonded compound that has typical 1H NMR signals for aromatic ring hydrogens and only one additional signal at δ 1.21, with an...
Apply the polygon-and-circle method to the cycloheptatrienyl anion and cation and explain whether each would be aromatic or not. (a) (b) Cycloheptatrienyl anion Cycloheptatrienyl cation
(a) What would you expect to be the major product when 1-phenylpropene reacts with HCl? (b) What product would you expect when it is subjected to oxymercuration demercuration?
Suppose you needed to synthesize m-chloroethylbenzene from benzene. You could begin by chlorinating benzene and then follow with a Friedel-Crafts alkylation using chloroethane and AlCl3, or you could...
Account for the following observations with mechanistic explanations. (a) At high concentration of ethoxide, the rate depends on both the allylic halide and ethoxide concentrations. (b) At low...
The following chlorides (Ph = phenyl) undergo solvolysis in ethanol at the relative rates given in parentheses. How can you explain these results? Ph Ph Ph (3 x 106) (0.08) (300)
Write mechanisms that account for the products of the following reactions: (a) (b) (-H20) HA
Outline all steps in a reasonable mechanism for the formation of isopropylbenzene from propene and benzene in liquid HF (just shown). Your mechanism must account for the product being...
Starting with benzene, outline a synthesis of each of the following: (a) Isopropylbenzene (b) tert-Butylbenzene (c) Propylbenzene (d) Butylbenzene (e) 1-tert-Butyl-4-chlorobenzene (f)...
Starting with toluene, outline a synthesis of each of the following: (a) m-Chlorobenzoic acid (b) p-Methylacetophenone (c) 2-Bromo-4-nitrotoluene (d) p-Bromobenzoic acid (e)...
Starting with aniline, outline a synthesis of each of the following: (a) p-Bromoaniline (b) o-Bromoaniline (c) 2-Bromo-4-nitroaniline (d) 4-Bromo-2-nitroaniline (e) 2,4,6-Tribromoaniline
Treating cyclohexene with acetyl chloride and AlCl3 leads to the formation of a product with the molecular formula C8H13ClO. Treating this product with a base leads to the formation of...
The tert-butyl group can be used as a blocking group in certain syntheses of aromatic compounds. (a) How would you introduce a tert-butyl group? (b) How would you remove it? (c) What advantage might...
Starting with benzene and the appropriate acyl chloride or acid anhydride, outline a synthesis of each of the following: (a) Butylbenzene (b) (c) (d) Diphenylmethane 9,10-Dihydroanthracene
(a) Which of the following halides would you expect to be most reactive in an SN2 reaction? (b) In an SN1 reaction? Explain your answers. Br
(a) Give IUPAC substitutive names for the seven isomeric aldehydes and ketones with the formula C5H10O. (b) Give structures and names (common or IUPAC substitutive names) for all the aldehydes and...
Write a detailed mechanism for the formation of an acetal from benzaldehyde and methanol in the presence of an acid catalyst.
Outline all steps in the mechanism for the formation of a cyclic acetal from acetone and ethylene glycol (1,2-ethanediol) in the presence of gaseous HCl.
Dihydropyran reacts readily with an alcohol in the presence of a trace of anhydrous HCl or H2SO4 to form a tetrahydropyranyl (THP) ether: (a) Write a plausible mechanism for this reaction. (b)...
Show how you might use thioacetal formation and Raney nickel desulfurization to convert: (a) cyclohexanone to cyclohexane and (b) benzaldehyde to toluene.
Triphenylphosphine can be used to convert epoxides to alkenes-for example, Propose a likely mechanism for this reaction. + (CgHs)3PO
Which compound in each of the following pairs has the higher boiling point? (Answer this problem without consulting tables.) (a) Pentanal or 1-pentanol (b) 2-Pentanone or 2-pentanol (c) Pentane or...
In addition to triphenylphosphine, assume that you have available as starting materials any necessary aldehydes, ketones, and organic halides. Show how you might synthesize each of the following...
Write structural formulas for the products formed when propanal reacts with each of the following reagents: (a) NaBH4 in aqueous NaOH (b) C6H5MgBr, then H3O+ (c) LiAlH4, then H2O (d) Ag2O, HO- (e)...
Give structures for compounds A-E. H2CrO (1) CHaMg (2) H20 Cyclohexanol acetone heat (1) 02 12) 2) Mes D (CH1202) (1) Ag20, HO (2) H20* C (C7H2) 2)(C,H120)
Dianeackerone is a volatile natural product isolated from secretory glands of the adult African dwarf crocodile. The compound is believed to be a pheromone associated with nesting and mating....
Outlined here is a synthesis of glyceraldehyde (Section 5.15A). What are the intermediates A-C and what stereoisomeric form of glyceraldehyde would you expect to obtain? PCC CH3OH, HA KMnO4, HO H2o ...
Compounds Y and Z are isomers with the molecular formula C10H12O. The IR spectrum of each compound shows a strong absorption band near 1710 cm-1. The 1H NMR spectra of Y and Z are given in Figs. 16.4...
When acetone is dissolved in water containing 18O instead of ordinary 16O (i.e., H2 18O instead of H2 16O), the acetone soon begins to acquire 18O and becomes The formation of this oxygen-labeled...
Outline syntheses of each of the following from acetoacetic ester and any other required reagents: (a) tert-Butyl methyl ketone (b) 2-Hexanone (c) 2, 5-Hexanedione (d) 4-Hydroxypentanoic acid (e)...
Outline syntheses of each of the following from diethyl malonate and any other required reagents: (a) 2-Methylbutanoic acid (b) 4-Methyl-1-pentanol (c) (d) OH
Outline a procedure for separating hexylamine from cyclohexane using dilute HCl, aqueous NaOH, and diethyl ether.
Outline a procedure for separating a mixture of benzoic acid, 4-methylphenol, aniline,and benzene using acids, bases, and organic solvents.
Diethylpropion (shown here) is a compound used in the treatment of anorexia. Propose a synthesis of diethylpropion starting with benzene and using any other needed reagents. Diethylpropion
The nucleosides shown in Figs. 25.4 and 25.5 are stable in dilute base. In dilute acid, however, they undergo rapid hydrolysis yielding a sugar (deoxyribose or ribose) and a heterocyclic base. (a)...
Write structural formulas showing how the keto form of uracil (Section 25.2) in mRNA can pair with adenine in DNA through hydrogen bond formation.
Draw a structural formula for each of the following compounds. (Several formulas may be possible in each case.) An alcohol with the molecular formula C5H10O
What nucleophile or base and what type of solvent could be used for the conversion of isobutyl bromide into each of the following compound? (CH3)TCHCH2SCH2CH3
Explain why 1-chlorobicyclol2.2.llheptane, even though it is a tertiary alkyl halide, is virtually unreactive in the S"1 reaction. (It has been estimated that it is 10-13 times as reactive as...
The reaction of butylamine, CH3(CH2)3NH2, with 1- bromobutane rn 60Vo aqueous ethanol follows the rate law rate = k[butylamine] [1 -bromobutane] The product of the reaction is (CH3CH2CH2CH2)2NH2+,...
Use the curved-arrow or fishhook notation to derive the major resonance structures for each of the following species. Determine which, if any, structure is the most important one in each case. (a)...
Tell whether each structure or term is a correct description of the L-sorbose structure shown here or a form with which it is in equilibrium. (b) a ketohexose (d) A ketohexose (f) An aldohexose CH2OH...
In the following acid-base reactions, 1. Determine which species are acting as electrophiles (acids) and which are acting as nucleophiles (bases). 2. Use the curved-arrow formalism to show the...
Draw the important resonance forms to show the delocalization of charges in the following ions. (a) (b) (c) (d) (e) (f) (g) (h) (i) (j) CH-C CH H-C-CH CHCH CH2 NH CHCH- CH CH CH-CH 3 CH3 CH CH CH CH...
Provide IUPAC names for the following compounds. (a) (CH3)2CHCH2CH3 (b) CH3-C(CH3)2-CH3 (c) (d) (e) (f) CH CH CHCH CH,CHCHCH le ' CH CH,CH, CH CH CH, CH CH C(CH CH,CH,CHCHCH, CH(CH2 CH CHCH,CH, CH)C...
For each structure, 1. Star (*) any asymmetric carbon atoms. 2. Label each asymmetric carbon as (R) or (S). 3. Draw any internal mirror planes of symmetry. 4. Label the structure as chiral or...
Write a balanced equation for each reaction. (a) (b) (c) (d) H SO, heat CH3 CH2CH-CH NaOC(CH3 3 Br Br Nal CHCH CH-CH acetone NaOH, heat CH3 CH CCH3 Br
Draw the NMR spectra you would expect for the following compounds. (a) (CH3)2CH-O-CH(CH3)2 (b) (c) Ph-CH(CH3)2 (d) (e) CI-CH2-CHC_O_CH3 - CH2COOCH CH CH2 COOCH2CH3
Nucleophilic aromatic substitution provides one of the common methods for making phenols. (Another method is discussed in Section 19-17.) Show how you would synthesize the following phenols, using...
Predict the mononitration products of the following aromatic compounds. (a) p-methylanisole (b) m-nitrochlorobenzene (c) p-chlorophenol (d) m-nitroanisole (e) (f) NH-C-CH CH o-methylacetanilide CHCNH...
Starting with benzene and any other reagents you need, show how you would synthesize the compound shown here.
A carboxylic acid has two oxygen atoms, each with two nonbonding pairs of electrons. (a) Draw the resonance forms of a carboxylic acid that is protonated on the hydroxyl oxygen atom. (b) Compare the...
(a) Propose a mechanism for the reaction of benzyl alcohol with acetyl chloride to give benzyl acetate. (b) Propose a mechanism for the reaction of benzoic acid with acetyl chloride to give acetic...
Predict the products of the following reactions. (a) Cyclopentanone + Br2 in acetic acid (b) 1-phenylethanol + excess I2 in base (c) (d) (e) (f) (g) (h) (i) CH (1) LDA CH CH,CH,CH,Br Ph TOH Ph (2)...
Like glucose, galactose mutarotates when it dissolves in water. The specific rotation of -D-galactopyranose is +150.7o, and that of the anomer is + 52.8o. When either of the pure anomers dissolves...
Which of the following are reducing sugars? Comment on the common name sucrose for table sugar. (a) methyl α-D-galactopyranoside (b) β-L-idopyranose (an aldohexose) (c)...
Treatment of either anomer of fructose with excess ethanol in the presence of a trace of HCl gives a mixture of the and anomers of ethyl-D-fructofuranoside. Draw the starting materials, reagents,...
Without referring to the chapter, draw the chair conformations of (a) -D-mannopyranose (the C2 epimer of glucose) (b) -D-allopyranose (the C3 epimer of glucose) (c) -D-galactopyranose (the C4 epimer...
Draw three-dimensional representations of the following amino acids. (a) L-phenylalanine (b) L-histidine (c) D-serine (d) L-tryptophan
Show how you would use bromination followed by amination to synthesize the following amino acids. (a) glycine (b) leucine (c) glutamic acid
Show how you would use a Strecker synthesis to make (a) Leucine (b) Valine (c) Aspartic acid
Show how the following amino acids might be formed in the laboratory by reductive amination of the appropriate -ketoacid (a) Alanine (b) Leucine (c) Serine (d) Glutamine
Draw the Newman projections for the unique staggered and eclipsed conformers of 2-methylbutane.
Compare the intermediate benzenonium ions for ortho, meta and para bromination of benzoic acid, and explain why the main product is m-bromobenzoic acid. C-OH benzoic aciod
Explain why it is not possible to prepare m-bromochlorobenzene or p-nitrobenzenesulfonic acid by carrying out two successive electrophilic aromatic substitutions.
Using Table 6.1, write an equation for each of the following substitution reactions: a. p-methylbenzyl chloride + sodium acetylide b. n-propyl bromide + sodium cyanide c. 2-iodopropane + sodium...
Provide an equation for the preparation of the following alkene from an alkyl halide. Do you anticipate problems with formation of other elimination or substitution reactions? Explain.
Write an equation for each of the following reactions: a. 2-methyl-2-butanol + HCl b. 3-pentanol + Na c. Cyclohexanol + PBr3 d. 2-phenylethanol + SOCl2 e. 1-methylcyclopentanol + H2SO4, heat f....
Show the steps in the mechanism for eq. 9.18. OCH3 (9.18) CH,OH (excess) -H-H+(catalyst) OCH3
Write a structural formula for each of the following compounds: a. diethylpropylamine b. N-methylbenzylamine c. sec-butylamine d. 1,5-diaminopentane e. N,N-dimethylaminocyclopentane f....
Benzoquinone is a very reactive dienophile. It reacts with 2- chloro-1,3-butadiene to give a single product, C10H9ClO2, in 95% yield. Write a structural formula for this product. Benzoquinone
Each of the following may be represented by at least one alternative resonance structure in which all the six-membered rings correspond to Kekulé forms of benzene. Write such a resonance form...
Write a structural formula for the most stable cyclohexadienyl cation intermediate formed in each of the following reactions. Is this intermediate more or less stable than the one formed by...
Write equations showing how you could prepare each of the following from benzene or toluene and any necessary organic or inorganic reagents. If an ortho, para mixture is formed in any step of your...
Suggest a suitable series of reactions for carrying out each of the following synthetic transformations: CH CH32 CO-H to SO3H CH3 CO H CH to (CH3)3 CH C to 0 OCH OCH O-N to OCH C(CH)s
What combination of acyl chloride or acid anhydride and arene would you choose to prepare each of the following compounds by a Friedel-Crafts acylation reaction? (a) CHsCCH2CGHs H C H C CH CH CH CO.H...
Evaluate the feasibility of the route as a method for preparing (a) 1-Butanol from butane (b) 2-Methyl-2-propanol from 2-methylpropane (c) Benzyl alcohol from toluene KOH light or heat
Suggest reaction sequences and reagents suitable for carrying out each of the following conversions. Two synthetic operations are required in each case. O to CH OH to CGHs to CaHs
Show how each of the following compounds can be synthesized from cyclopentanol and any necessary organic or inorganic reagents. In many cases the desired compound can be made from one prepared in an...
Given the starting material 1-methyl-1,2-epoxycyclopentane, of absolute configuration as shown, decide which one of the compounds A through C correctly represents the product of its reaction with...
Predict the product of the reaction of propanal with each of the following: (a) Lithium aluminum hydride (b) Sodium borohydride (c) Hydrogen (nickel catalyst) (d) Methylmagnesium iodide, followed by...
Each of the following reactions has been reported in the chemical literature and gives a single product in good yield. What is the product in each reaction? (a) (b) (c) (d) (e) (f) CH2 CH(CH2)8CO2H...
Write the structure of the product formed on reaction of aniline with each of the following: (a) Hydrogen bromide (b) Excess methyl iodide (c) Acetaldehyde (d) Acetaldehyde and hydrogen (nickel...
Write ionic and net ionic equations for the following reactions: (a) (b) (c) AgNO,(aq) + Na-SO4(aq )- BaCl2 (aq) + ZnSO4 (aq)- (NH4)2CO3(aq) + CaCl2(aq)
Which of the following species are isoelectronic with each other? C, Cl-, Mn2+, B-, Ar, Zn, Fe3+, Ge2+.
Write the Lewis dot symbols of the reactants and products in the following reactions. (First balance the equations.) (a) Sr + Se SrSe (b) Ca + H2 CaH2 (c) Li + N2 Li3N (d) Al + S Al2S3
The phase diagram of sulfur is shown here. (a) How many triple points are there? (b) Monoclinic and rhombic are two allotropes of sulfur. Which is more stable under atmospheric conditions? (c)...
At 27C, the vapor pressure of pure water is 23.76 mmHg and that of an urea solution is 22.98 mmHg. Calculate the molality of solution.