OCHEM II QUIZZES FOR TEST 2

Aromatic rings are stable and it is called the aromaticity. And there are four conditions for the aromaticity. Please choose all four conditions among below:

- Cyclic system should be conjugated pi system - Every carbon in the ring should have an extra p orbital - The number of pi electron on the ring should satisfy 4n+2 rule. - It must satisfy the Huckel's rule - The ring has to be flat - It must be cyclic

please choose every correct statement for the Diels-alder reaction

- Diels-alder reaction is between a diene and a dienophile - Diels-Alder reaction is [4+2] cycloaddition - Diels-Alder is a concerted mechanism - Diels-Alder reaction is a cycloaddition mechanism

Please choose every correct one.

- Friedel-Craft alkylation is for alyklation on aromatic ring - Friedel-Craft alkylation is using AlCl3 for Lewis acid - AlCl3 is for making carbocation or acyl cation from alkyl halides or acyl halides - Friedel-Craft acylation is using AlCl3 for lewis acid

Please choose every correct statement about the kinetic control for the reaction of 1,3-butadiene with HCl

- Kinetic control of the reaction is based on the more stable intermediate and less stable product. - Kinetic control of the reaction give 3-chlorobut-1-ene as the major product

Please choose every correct statement for the conjugated pi system

- The conjugate pi system is more stable than the non-conjugated system - The conjugated pi-system is more stable than non-conjugated system, since the pi electron can be delocalized along the conjugated system - The conjugated pi system is more stable since it can have resonance structures

Please choose every correct statement for pyridine below:

- This a flat cyclic molecule - Pyridine is classified as a heterocyclic -Pyridine is an aromaticmolecule - For its aromaticity, pyridine is considered to have six pi electron with the lone pair electron on nitrogen

The benzene (C6H6) is stablelsince

- it has six pi electron - every carbon in the ring is sp2 hybridized - it has resonance structures

In the reaction of 1,3-butadiene with HCl, it gives two products. Please write the IUPAC name of either product.

1-chloro-2-butene

Please answer the question for the reactions listed below: A) o-Nitroanisole + CH3Cl/AlCl3 --> Please choose every product of reaction

2-methyl-6-nitroanisole 4-methyl-6-nitroanisole

Please answer the question for the reactions listed below: A) m-Nitrotoluene + Br2/FeBr3 --> Please choose every product of reaction

4-bromo-5-nitrotoluene 2-bromo-5-nitrotoluene

Please answer the question for the reactions listed below: A) m-hydroxyacetophenone + HNO3/H2SO4 --> Please choose every product of reaction.

4-hydroxy-3-nitroacetophenone

Molecular orbitals of 1,3-butadiene are listed below: Which one is HOMO of 1,3-butadiene in ground state?

A)

The diels-alder reaction is listed below: Which one is the right structure of product with stereochemistry

A)

Please choose every electron-withdrawing group from the table

A), C), D)

In the reaction of 1,3-butadiene with HCl, what is the first intermediate? Choose every correct one.

A), D)

please choose molecules having conjugated pi-system

A, D, F,E

Bromination on benzene ring can be done as below: Please choose every correct statement.

Br2/FeBr3 produces the bromonium ion The role of FeBr3 is the Lewis acid to remove the bromide from Br2.

In the reaction of 1,3-butadiene with HCl, the first intermediate (allyl cation) will be resonated to another structure,

C)

The following are the diene can be used for the diels-alder reaction Which one is the worst one?

C)

Please choose every ring having aromaticity

C), H), E), D)

Please choose every wrong structure of sigma complex among below:

C,D,E,F

Please choose every resonance structure of cyclopentadienyl anion

C,E, G, A, F

Please choose the right reagent for making chlorobenzene from benzene.

Cl2 with AlCl3 Cl2 with FeCl3

Please choose which one is the most stable intermediate?

D), A)

The followings are the dienes which can be used for the diels-alder reaction. Which diene is the best for the Diels-alder reaction?

E)

For the diels-alder reaction, dienen and dienophile like to have some substituents enhancing the reaction. Please choose every good dienophile with reasons for the reaction from the table below:

E) and electron-withdrawing group D) ad electron-withdrawing group

Please choose every correct one, which can be used for describing aromatic ring.

E, C, G, F, A

Please choose every resonance structure of cycloheptatrienyl cation

EVERYTHING BUT H AND D

Please choose every non-aromatic ring

F, B

Please choose every wrong resonance structure of antracene

F,E, B

Please choose every antiaromatic ring

G, A

1,3-butadiene reacts with HCl, which is an electrophilic addition reaction. Which one is the electrophile in the reaction?

H+

Cyclohexa-1,4-dience is non-aromatic. It is due to

It is not a cycle, but not conjugated pi-system

Please choose every correct statement on the kinetic control.

Kinetic control means that the reaction needs mild condition and a short reaction time.

Please write the IUPAC name for A) with stereochemistry

NOT SURE 1,3-pentadiene

Please write the IUPAC name for E) with stereochemistry

NOT SURE 1,5-heptadiene-3-yne

Nitration on aromatic ring is done as below: Please choose every correct statement.

Nitric acid will lose water after receiving the proton Sulfuring acid is stronger an it donates the proton to oxygen in nitric acid.

Please choose the right reagent for making benzenesulfonic acid from benzene ring.

SO3 with sulfuric acid

Please choose every correct statement.

The aromatic rings forms the sigma complex after having incoming electrophile. Aromatic ring doesn't want to lose the aromaticity in the reaction. Aromatic ring has high density of electron and it makes electrophilic reaction possible

in the reaction of 1,3-butadiene with HCl,it gives two products: Between two products, which is more stable and why? Choose the major product and write the name of rule you have to use.

Y, zaitsev's rule

Please choose every electron-donating group.

a d e l m s

Please choose every ortho and para directing group.

a d e l m s

A) acetyl chloride + 1) AlBr3, 2) benzene Please write the name of product from the reaction A).

acetophenone

is the same as RCOCl, and it is called acyl chloride. Please write the name for CH3COCl.

acetyl chloride

Please write whether c) is aromatic, anti-aromatic, or non-aromatic

anti-aromatic

Please write whether B) is aromatic, anti-aromatic, or non-aromatic

aromatic

Please choose every electron-withdrawing group. Write them without spaces.

b c g h i j k no p q t

Please choose every meta directing group.

b g h i n p q t

AROMATICIII.bmp Please write the common of C)

benzaldehyde

AROMATICIII.bmp Please write the common of A)

benzenesulfonic acid

Please answer the question for the structures below: Please write the name of G).

benzimidazole

AROMATICIII.bmp Please write the common of G)

benzoic acid

Please write the name of compound which undergoes bromination most slowly among molecules: bromobenzene, benzaldehyde, benzene, or benzonitrile

benzonitrile

B) acetyl chloride + 1) AlBr3, 2) benzene Please write the name of product from the reaction B). 'C6H5' is phenyl group.

benzophenone

is the same as RCOCl, and it is called acyl chloride. Please write the name for C6H5COCl.

benzoyl chloride

Please write the name of the compound that undergoes Friedel-Craft Acylation among the following molecules: bromobenzene, benzaldehyde, benzene, or benzonitrile

biphenyl

Which of the following can be used as the electrophile in the electrophilic aromatic substitution reaction on aromatics? Choose every correct one.

carbocations sulfur trioxoide acyl cation nitronium ion

The structure below is the product of Diels-alder reaction. Please write the name of diene used for making the product above.

cyclohexa-1,3-diene

B) Benzyl chloride + 1) AlCl3, 2) benzene Please write the name of product from reaction B).

diphenylmethane

please write the common name of F)

furan

Please answer the question for the structures below: Please write the name of A).

imidazole

C) 1-bromopentane + 1) AlBr3, 2) benzene Please write the name of product from reaction C). There is rearrangement occurred.

isopropylbenzene

Please answer the question for the reactions listed below: A) Acetophenone + HNO3/H2SO4 --> Please choose every product of reaction.

m-nitroacetophenone

Please answer the question for the reactions listed below: A) Nitrobenezene + SO3/H2SO4 --> Please choose every product of reaction.

m-nitrobenzenesulfonic acid

AROMATICIII.bmp Please write the common of D)

m-nitrostyrene

AROMATICIII.bmp Please write the common of H)

m-xylene

Electrophilic addition reaction on 1,3-butadiene follows the regiospecific rule. What is the name of rule? Please write the name.

markovnikov's rule

Please answer the question for the structures below: Please write the name of D).

naphthalene

Please write the name of the compound which shouldn't undergo Friedel-Craft Alkylation among the following molecules: acetophenone, anisole, nitrobenzene, or phenol.

nitrobenzene

Please answer the question for the reactions listed below: A) m-cyanobenzaldehyde + CH3COCl/AlCl3 --> Please choose every product of reaction.

no reaction

Bromination of benzene is done through the formation of sigma complexes. is the sigma complex aromatic, anti-aromatic, or non-aromatic? Please write the answer.

non-aromatic

Please write whether A) is aromatic, anti-aromatic, or non-aromatic

non-aromatic

Please answer the question for the reactions listed below: A) Bromobenezene + SO3/H2SO4 --> Please choose every product of reaction.

o-bromobenzenesulfornic acid p-bromobenzenesulfonic acid

AROMATICIII.bmp Please write the common of F)

o-chloroanisole

AROMATICIII.bmp Please write the common of E)

o-nitroacetophenone

AROMATICIII.bmp Please write the common of I)

p-chloroaniline

Please answer the question for the reactions listed below: A) Aniline + Cl2/FeCl3 --> Please choose every product of reaction.

p-chloroaniline o-chloroaniline

Please write the name of the compound which undergoes bromination faster among acetophenone, anisole, nitrobenzene, or phenol.

phenol

Please answer the question for the structures below: Please write the name of C).

purin

Please answer the question for the structures below: Please write the name of E).

pyridine

Please answer the question for the structures below: Please write the name of B).

pyrole

Please answer the question for the structures below: Please write the name of F).

quinoline

Please choose every correct statement for imidazol

sp3 nitrogen contributes the lone pair electron to the pi-system of the ring

cycloocta-1,3,5,7-tetraene is not aromatic, since

the ring is not flat.

If the reaction gives two different intermediates and two products, they can be called either kinetic control or thermodynamic control product. Which control is based on less stable intermediate and more stable product? Write the name of control.

thermodynamic control

A) Methyl bromide + 1) AlBr3, 2) benzene Please write the name of product from reaction A).

toluene

AROMATICIII.bmp Please write the common of B)

toluene