Textbook Question
Show how you would synthesize the following compound from alkyl halides, vinyl halides, and aryl halides containing no more than six carbon atoms.
(c) trans-oct-3-ene
1073
views
Ch.10 - Structure and Synthesis of Alcohols
Wade9th EditionOrganic ChemistryISBN: 9780135213728
Not the one you use?Change textbookSelect a different textbook
Table of contents
- Ch.1 - Structure and Bonding107
- Ch. 2 - Acids and Bases; Functional Groups115
- Ch.3 - Structure and Stereochemistry of Alkanes100
- Ch.4 - The Study of Chemical Reactions99
- Ch.5 - Stereochemistry93
- Ch.6 - Alkyl Halides; Nucleophilic Substitution118
- Ch. 7 - Structure and Synthesis of Alkenes; Elimination158
- Ch.8 - Reactions of Alkenes171
- Ch.9 - Alkynes91
- Ch.10 - Structure and Synthesis of Alcohols143
- Ch.11 - Reactions of Alcohols104
- Ch. 12 - Infrared Spectroscopy and Mass Spectrometry22
- Ch. 13 - Nuclear Magnetic Resonance Spectroscopy45
- Ch. 14 - Ethers, Epoxides, and Thioethers72
- Ch. 15 - Conjugated Systems, Orbital Symmetry, and Ultraviolet Spectroscopy89
- Ch. 16 - Aromatic Compounds74
- Ch. 17 - Reactions of Aromatic Compounds126
- Ch. 18 - Ketones and Aldehydes193
- Ch. 19 - Amines129
- Ch. 20 - Carboxylic Acids77
- Ch. 21 - Carboxylic Acid Derivatives141
- Ch. 22 - Condensations and Alpha Substitutions of Carbonyl Compounds175
- Ch. 23 - Carbohydrates and Nucleic Acids93
- Ch. 24 - Amino Acids, Peptides, and Proteins54
Chapter 10, Problem 19c
Show how you would synthesize the following alcohol by adding Grignard reagents to ethylene oxide.
(c) 
Verified step by step guidance1
Step 1: Identify the target alcohol structure. The alcohol shown has a cyclohexane ring with a methyl group and a CH2CH2OH group attached to the same carbon. This suggests that the synthesis involves forming a secondary alcohol at the carbon attached to the ring.
Step 2: Recognize the role of ethylene oxide in the synthesis. Ethylene oxide is an epoxide that reacts with Grignard reagents to form alcohols. The reaction involves nucleophilic attack by the Grignard reagent on the epoxide, followed by protonation to yield the alcohol.
Step 3: Determine the Grignard reagent needed. To form the CH2CH2OH group, the Grignard reagent must contain the cyclohexane ring and the methyl group already attached to the same carbon. This can be achieved by using cyclohexylmethyl magnesium bromide (C6H11CH2MgBr) as the Grignard reagent.
Step 4: Perform the reaction. Add the Grignard reagent (C6H11CH2MgBr) to ethylene oxide under anhydrous conditions. The nucleophilic carbon in the Grignard reagent will attack the less hindered carbon of the epoxide, opening the ring and forming a new C-C bond.
Step 5: Protonate the intermediate. After the epoxide ring opens, the resulting alkoxide intermediate is protonated using a mild acid (e.g., HCl or H2O) to yield the final alcohol product, which matches the target structure.
Verified video answer for a similar problem:
This video solution was recommended by our tutors as helpful for the problem above.
Video duration:
2mWas this helpful?
Key Concepts
Here are the essential concepts you must grasp in order to answer the question correctly.
Grignard Reagents
Grignard reagents are organomagnesium compounds represented as R-MgX, where R is an organic group and X is a halogen. They are highly reactive and serve as nucleophiles in organic synthesis, allowing for the formation of carbon-carbon bonds. When added to electrophiles, such as carbonyl compounds or epoxides, they can facilitate the synthesis of alcohols and other functional groups.
Recommended video:
Guided course
02:12
Carbonation of Grignard Reagents
Ethylene Oxide
Ethylene oxide is a three-membered cyclic ether that is highly reactive due to its strained ring structure. It can undergo nucleophilic attack, making it a useful substrate for reactions with Grignard reagents. When a Grignard reagent attacks ethylene oxide, it opens the epoxide ring, leading to the formation of an alcohol after subsequent protonation.
Recommended video:
Guided course
03:40Strong oxidizing agents
Nucleophilic Attack
Nucleophilic attack is a fundamental reaction mechanism in organic chemistry where a nucleophile donates an electron pair to an electrophile, forming a new bond. In the context of Grignard reagents and ethylene oxide, the nucleophile (Grignard reagent) attacks the electrophilic carbon in the epoxide, resulting in ring opening and the formation of a new carbon-carbon bond, ultimately leading to the desired alcohol.
Recommended video:
Guided course
08:27Nucleophilic Addition
Related Practice
Textbook Question
Show how you would synthesize the following compound from alkyl halides, vinyl halides, and aryl halides containing no more than six carbon atoms.
(a) octane
1128
views
Textbook Question
A formate ester, such as ethyl formate, reacts with an excess of a Grignard reagent to give (after protonation) secondary alcohols with two identical alkyl groups.
(a) Propose a mechanism to show how the reaction of ethyl formate with an excess of allylmagnesium bromide gives, after protonation, hepta-1,6-dien-4-ol.
2089
views
Textbook Question
Acetylide ions also add to ethylene oxide much like Grignard and organolithium reagents. Predict the products obtained by adding the following acetylide ions to ethylene oxide, followed by a dilute acid workup.
(a) HC≡C:–
(b) CH3CH2–C≡C:–
1360
views
Textbook Question
A formate ester, such as ethyl formate, reacts with an excess of a Grignard reagent to give (after protonation) secondary alcohols with two identical alkyl groups.
(b) Show how you would use reactions of Grignard reagents with ethyl formate to synthesize the following secondary alcohols.
(i) pentan-3-ol
(ii) diphenylmethanol
(iii) trans,trans-nona-2,7-dien-5-ol
2291
views
Textbook Question
Show how you would synthesize the following alcohol by adding Grignard reagents to ethylene oxide.
(a) 2-phenylethanol
1420
views