The major product of the reaction of methylenecyclohexane

Give IUPAC names for the following alkyl halides: Equation Transcription: Text Transcription: CH_3CH_2CH_2CH_2I CH_3 CH_3CHCH_2CH_2Cl CH_3 BrCH_2CH_2CH_2CCH_2Br CH_3 CH_3 CH_3CCH_2CH_2Cl CH_2CH_2Cl CH_3CHCHCH_2CH_3 CH_3CHCH_2CH_2CHCH_3

Draw structures corresponding to the following IUPAC names: (a) 2-Chloro-3,3-dimethylhexane (b) 3,3-Dichloro-2-methylhexane (c) 3-Bromo-3-ethylpentane (d) 1,1-Dibromo-4-isopropylcyclohexane (e) 4-sec-Butyl-2-chlorononane (f) 1,1-Dibromo-4-tert-butylcyclohexane

What products would you expect from the reaction of 4,4-dimethylcyclohexene with NBS?

Draw three resonance forms for the cyclohexadienyl radical.

The major product of the reaction of methylenecyclohexane with N-bromosuccinimide is 1-(bromomethyl)cyclohexene. Explain. ________________ Equation Transcription: Text Transcription: CH_2 hv,CCl_4 CH_2Br

What products would you expect from reaction of the following alkenes with NBS? If more than one product is formed, show the structures of all. ________________ Equation Transcription: Text Transcription: CH_3 CH_3 CH_3CHCH=CHCH_2CH_3

How would you prepare the following alkyl halides from the corresponding alcohols? Equation Transcription: Text Transcription: CH_3CCH_3 CH_3 CH_3CHCH_2CHCH_3 CH_3 CH_3 BrCH_2CH_2CH_2CH_2CHCH_3

How strong a base would you expect a Grignard reagent to be? Look at Table 9-1 on page 276, and predict whether the following reactions will occur as written. (The \(\mathrm pK_\mathrm a\) of \(\mathrm{NH_3}\) is 35.) (a) \(\mathrm{CH_3MgBr+H-C \equiv C-H \rightarrow CH_4+H-C \equiv C-MgBr}\) (b) \(\mathrm{CH_3MgBr+NH_3 \rightarrow CH_4+H_2N-MgBr}\) Equation Transcription: Text Transcription: pK_a NH_3 CH_3MgBr+H-C equiv C-H rightarrow CH_4+H-C equiv C-MgBr CH_3MgBr+NH_3 rightarrow CH_4+H_2N-MgBr

How might you replace a halogen substituent by a deuterium atom if you wanted to prepare a deuterated compound? Equation Transcription: Text Transcription: CH_3CHCH_2CH_3 CH_3CHCH_2CH_3

How would you carry out the following transformations using an organocopper coupling reaction? More than one step is required in each case. Equation Transcription: Text Transcription: CH_3 CH_3CH_2CH_2CH_2Br CH_3CH_2CH_2CH_2CH_2CH_2CH_2CH_3 CH_3CH_2CH_2CH=CH_2 CH_3CH_2CH_2CH_2CH_2CH_2CH_2CH_2CH_2CH_3

Rank both sets of compounds in order of increasing oxidation level: Equation Transcription: Text Transcription: CH_3CN CH_3CH_2NH_2 H_2NCH_2CH_2NH_2

Tell whether each of the following reactions is an oxidation, a reduction, or neither. Equation Transcription: Text Transcription: CH_3CH_2CH NaBH_4 H_2O CH_3CH_2CH_2OH BH_3 NaOH,H_2O_2

Give IUPAC names for the following alkyl halides (green = Cl):

Show the product(s) of reaction of the following alkenes with NBS:

The following alkyl bromide can be prepared by reaction of the alcohol (S)-2-pentanol with \(\mathrm{PBr_3}\). Name the compound, assign (R) or (S) stereochemistry, and tell whether the reaction of the alcohol results in the same stereochemistry or a change in stereochemistry (reddish brown = Br). Equation Transcription: Text Transcription: PBr_3

Draw the electron-pushing mechanism for each radical reaction below. Identify each step as initiation, propagation, or termination. ________________ Equation Transcription: Text Transcription: Br_2 Cl_2 Cl_2

Draw the electron-pushing mechanism for the propagation steps of the allylic bromination reactions below. You may omit NBS in your mechanism, and use \(\mathrm{Br \cdot}\) and \(\mathrm{Br_2}\). Equation Transcription: Text Transcription: Br{cdot} Br_2 CH_3 CH_2Br

The formation of \(\mathrm{Br_2}\) from NBS first involves the reaction of NBS with HBr to form an iminol intermediate and molecular bromine. The intermediate then undergoes acid-catalyzed tautomerism to form succinimide, the byproduct of the reaction. Propose a curved-arrow mechanism for the conversion of NBS into succinimide that also accounts for the formation of \(\mathrm{Br_2}\). ________________ Equation Transcription: Text Transcription: Br_2 Br_2 N-Br+Hbr N+Br_2

In light of the fact that tertiary alkyl halides undergo spontaneous dissociation to yield a carbocation plus halide ion (see Problem 10-45), propose a mechanism for the following reaction. Equation Transcription: Text Transcription: CH_3 H_3C-C-Br CH_3 H_2O 50^oC CH_3 H_3C-C-OH CH_3

Alkyl halides can be reduced to alkanes by a radical reaction with tributyltin hydride, \(\mathrm {(C_4H_9)_3SnH}\), in the presence of light \((hv)\). Propose a radical chain mechanism by which the reaction might occur. The initiation step is the light-induced homolytic cleavage of the \(\mathrm {Sn-H}\) bond to yield a tributyltin radical. \(\mathrm{R}-\mathrm{X}+\left(\mathrm{C}_{4} \mathrm{H}_{9}\right)_{3} \mathrm{SnH} \stackrel{h \nu}{\longrightarrow} \mathrm{R}-\mathrm{H}+\left(\mathrm{C}_{4} \mathrm{H}_{9}\right)_{3} \mathrm{Sn} \mathrm{X}\) ________________ Equation Transcription: Text Transcription: (C_4H_9)_3SnH (hv) Sn-H R-X+(C_4H_9)_3SnH R-H+(C_4H_9)_3SnX

Name the following alkyl halides: Equation Transcription: Text Transcription: H_3C CH_3CHCHCHCH_2CHCH_3 CH_3 CH_3CH=CHCH_2CHCH_3 CH_3 CH_3CCH_2CHCHCH_3 CH_3 CH_2Br CH_3CH_2CHCH_2CH_3 ClCH_2CH_2CH_2CCCH_2Br

Draw structures corresponding to the following IUPAC names: (a) 2,3-Dichloro-4-methylhexane (b) 4-Bromo-4-ethyl-2-methylhexane (c) 3-Iodo-2,2,4,4-tetramethylpentane (d) cis-1-Bromo-2-ethylcyclopentane

Draw and name all of the monochlorination products that you might obtain from the radical chlorination of the compounds below. Which of the products are chiral? Are any of the products optically active? (a) 2-methylbutane (b) methylcyclopropane (c) 2,2-dimethylpentane

How would you prepare the following compounds, starting with cyclopentene and any other reagents needed? (a) Chlorocyclopentane (b) Methylcyclopentane (c) 3-Bromocyclopentene (d) Cyclopentanol (e) Cyclopentylcyclopentane (f) 1,3-Cyclopentadiene

Predict the product(s) of the following reactions: Equation Transcription: Text Transcription: H_3C CH_3CH_2CH_2CH_2OH SOCl_2 hv, CCl_4 PBr_3 CH_3CH_2CHBrCH_3 H_2O CH_3CH_2CH_2CH_2Br CH_3CH_2CH_2CH_2Br (CH_3)_2CuLi

A chemist requires a large amount of 1-bromo-2-pentene as starting material for a synthesis and decides to carry out an NBS allylic bromination reaction. What is wrong with the following synthesis plan? What side products would form in addition to the desired product? ________________ Equation Transcription: Text Transcription: CH_3CH_2CH=CHCH_3 hv, CCl_4 CH_3CH_2CH=CHCH_2Br

What product(s) would you expect from the reaction of 1-methylcyclohexene with NBS? Would you use this reaction as part of a synthes Equation Transcription: Text Transcription: CH_3 hv, CCl_4

What product(s) would you expect from the reaction of 1,4-hexadiene with NBS? What is the structure of the most stable radical intermediate?

What product would you expect from the reaction of 1-phenyl-2-butene with NBS? Explain.

Rank the compounds in each of the following series in order of increasing oxidation level: Equation Transcription: Text Transcription: CH_3CH=CHCH_3 CH_3CH_2CH=CH_2 CH_3CH_2CH_2CH CH_3CH_2CH_2COH CH_3CH_2CH_2NH_2 CH_3CH_2CH_2Br CH_3CCH_2Cl BrCH_2CH_2CH_2Cl

Which of the following compounds have the same oxidation level, and which have different levels?

Tell whether each of the following reactions is an oxidation, a reduction, or neither: ________________ Equation Transcription: Text Transcription: CH_3CH_2OH CrO_3 CH_3CH H_2C=CHCCH_3+NH_3 H_2NCH_2CH_2CCH_3 CH_3CH_2CHCH_3 H_2O CH_3CH_2CH_2CH_3

Sort the radicals below from most stable to least stable.

Alkylbenzenes such as toluene (methylbenzene) react with NBS to give products in which bromine substitution has occurred at the position next to the aromatic ring (the benzylic position). Explain, based on the bond dissociation energies in Table 6-3 on page 170. Equation Transcription: Text Transcription: CH_3 hv,CCl_4 CH_2Br

Draw resonance structures for the benzyl radical, \(\mathrm {C_6H_5CH_2 \cdot}\), the intermediate produced in the NBS bromination reaction of toluene (Problem 10-35). Equation Transcription: Text Transcription: C_6H_5CH_2{cdot}

Draw resonance structures for the following species: Equation Transcription: Text Transcription: CH_3CH=CHCH=CHCH=CHCH_2 CH_3C equiv N-O

(S)-3-Methylhexane undergoes radical bromination to yield optically inactive 3-bromo-3-methylhexane as the major product. Is the product chiral? What conclusions can you draw about the radical intermediate?

Assume that you have carried out a radical chlorination reaction on (R)-2-chloropentane and have isolated (in low yield) 2,4-dichloropentane. How many stereoisomers of the product are formed, and in what ratio? Are any of the isomers optically active? (See Problem 10-38.)

How would you carry out the following syntheses?

The syntheses shown here are unlikely to occur as written. What is wrong with each? Equation Transcription: Text Transcription: CH_3CH_2CH_2F H_3O^+ CH_3CH_2CH_3 CH_2 CH_3 hv,CCl_4 CH_2 CH_3 (CH_3)_2CuLi CH_3

Why do you suppose it’s not possible to prepare a Grignard reagent from a bromo alcohol such as 4-bromo-1-pentanol? Give another example of a molecule that is unlikely to form a Grignard reagent. Equation Transcription: Text Transcription: CH_3CHCH_2CH_2OH CH_3CHCH_2CH_2CH_2OH

Addition of HBr to a double bond with an ether \(\mathrm {(-OR)}\) substituent occurs regiospeciically to give a product in which the \(\mathrm {-Br}\) and \(\mathrm {-OR}\) are bonded to the same carbon. Draw the two possible carbocation intermediates in this electrophilic addition reaction, and explain using resonance why the observed product is formed. Equation Transcription: Text Transcription: OCH_3 OCH_3

Identify the reagents a–c in the following scheme: Equation Transcription: Text Transcription: CH_3 CH_3 CH_3 CH_3 CH_3

Tertiary alkyl halides, \(\mathrm {R_3CX}\), undergo spontaneous dissociation to yield a carbocation, \(\mathrm {R_3C^+}\), plus halide ion. Which do you think reacts faster, \(\mathrm {(CH_3)_3CBr}\) or \(\mathrm {H_2C=CHC(CH_3)_2Br}\)? Explain. Equation Transcription: Text Transcription: R_3CX R_3C^+ (CH_3)_3CBr H_2C=CHC(CH_3)_2Br

Carboxylic acids \(\mathrm {(RCO_2H;p}K_\mathrm a \approx 5)\) are approximately \(10^{11}\) times more acidic than alcohols \(\mathrm {(ROH;p} K_ \mathrm a \approx 16)\). In other words, a carboxylate ion \(\mathrm {(RCO_2^-)}\) is more stable than an alkoxide ion \(\mathrm {(RO^-)}\). Explain, using resonance. Equation Transcription: Text Transcription: (RCO_2H;pK_a approx 5) 10^{11} (ROH;pK_a approx 16) (RCO_2^-) (RO^-)

How might you use a Suzuki–Miyaura reaction to prepare the biaryl compounds below? In each case, show the two potential reaction partners. Equation Transcription: Text Transcription: CH_3O OCH_3 CO_2CH_3 NH_2 CH_3 CH_3O CH_3O CH_3O

The relative rate of radical bromination is 1:82:1640 for \(\mathrm {1^o:2^o:3^o}\) hydrogens, respectively. Draw all of the monobrominated products that you might obtain from the radical bromination of the compounds below. Calculate the relative percentage of each. (a) methylcyclobutane (b) 3,3-dimethylpentane (c) 3-methylpentane Equation Transcription: Text Transcription: 1^o:2^o:3^o

Choose the alcohol from each pair below that would react faster with HX to form the corresponding alkyl halide.

Predict the product and provide the entire catalytic cycle for the Suzuki–Miyaura reactions below. ________________ Equation Transcription: Text Transcription: CO_2H B(OH)_2 Pd(OAc)_2 CH_3O (HO)_2B OCH_3 Pd(OAc)_2