Electrophilic Aromatic Substitution [PDF]

Electrophilic Aromatic Substitution: Friedel-Crafts Acylation. Study Questions. 1) A carbocation produced during a Fried

0 downloads 5 Views 268KB Size

Recommend Stories


Aromatic electrophilic substitution
Never let your sense of morals prevent you from doing what is right. Isaac Asimov

Lecture 15 Aromatic Nucleophilic Substitution
Don't count the days, make the days count. Muhammad Ali

How amino and nitro substituents direct electrophilic aromatic substitution in benzene: an
You're not going to master the rest of your life in one day. Just relax. Master the day. Than just keep

Molecular Orbital Study of Electrophilic Substitution of Allylmetal Compounds
There are only two mistakes one can make along the road to truth; not going all the way, and not starting.

Synthesis of Functional Fluorescent BODIPY‐based Dyes through Electrophilic Aromatic
The only limits you see are the ones you impose on yourself. Dr. Wayne Dyer

Substitution
Love only grows by sharing. You can only have more for yourself by giving it away to others. Brian

Sensory Substitution is Substitution
You can never cross the ocean unless you have the courage to lose sight of the shore. Andrè Gide

Substitution
And you? When will you begin that long journey into yourself? Rumi

Nucleophilic and Electrophilic Trifluoromethylation - School of [PDF]
Preparation of the Ruppert–Prakash Reagent: TMSCF. 3. Ruppert, I. et. al. Tetrahedron Lett. 1984, 25, 2195. Prakash, G. K. S. et. al. Org. Synth. 1995, 72, 232. Prakash, G. K. S. et. al. J. Org. Chem. 2003, 68, 4457. ↑. Ozone. Depleting. ↑. Tox

Electrophilic activation of allenenes and allenynes
Never wish them pain. That's not who you are. If they caused you pain, they must have pain inside. Wish

Idea Transcript


Experiment 16 Electrophilic Aromatic Substitution: Friedel-Crafts Acylation Study Questions 1) A carbocation produced during a Friedel-Crafts alkylation may undergo rearrangement. What rearranged product might you expect from the reaction below?

Answer:

2) Predict the major mononitration products of methyl benzoate and of toluene. O

O

CH3 HNO3

HNO3

H2SO4

Methyl benzoate

H2SO4

Toluene

Answer:

3) Predict the major monoalkylation products you would expect to obtain from the reaction of the following compounds with iodomethane (CH3I) and AlCl3. (Note: Iodomethane is one of the most common methylating agents. You are probably more accustomed to seeing alkyl halides that contain bromine and chlorine; in this case they are not used because both chloromethane and bromomethane are gases at room temperature).

Answer:

15

Experiment 16: Electrophilic Aromatic Substitution Br

OH

OH

Br

a.

The site between OH and Br is too hindered to allow addition Br

H3C CH3

+

+

b.

Br CH3

c.

CH3

No reaction (this group is too deactivating to permit Friedel-Crafts)

d.

CH3

4) What product(s) would you expect to obtain from the following reactions? O +

a.

AlCl3 Cl

O

O AlCl3

+

b.

O Br O

O

c.

+

O AlCl3 O

Answer:

5) The NMR spectrum of ferrocene is shown below (taken from SDBS). Explain why the aromatic protons show a single band at 4.2 ppm. 16

Experiment 16: Electrophilic Aromatic Substitution

Answer: Because they are all equivalent. 6) The NMR spectrum of monoacetylferrocene is shown below (taken from SDBS). What would the NMR of diacetylferrocene look like?

Answer: The “c” peak would disappear and the others would double in intensity. 7) A student performed this experiment and obtained the NMR spectrum shown below. What other impurities are present? What is the molar ratio of ferrocene to monoacetylferrocene in the crude product? What percent of the crude product is ferrocene vs. monoacetylferrocene?

17

Experiment 16: Electrophilic Aromatic Substitution

Answer: Impurities present are CDCl3 (7.26 ppm), acetone (2.17 ppm), and water (1.60 ppm). For product ratios, the two easiest peaks to use are at 4.21 (5H in monoacetylferrocene) and 4.16 (10H in ferrocene).

18

Smile Life

When life gives you a hundred reasons to cry, show life that you have a thousand reasons to smile

Get in touch

© Copyright 2015 - 2024 PDFFOX.COM - All rights reserved.