Textbook Question
Using an appropriate tosylate intermediate, synthesize the following molecules starting from the appropriate alcohol.
(b)
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12. Alcohols, Ethers, Epoxides and Thiols
Leaving Group Conversions - Sulfonyl Chlorides
Problem 106k(iii,iv)
Textbook Question
Predict the product(s) that would result when molecules (a)–(p) are allowed to react under the following conditions: (iii) SOCl₂ , NEt₃, and (iv) 1. TsCl, Et₃N 2. NaCN. If no reaction occurs, write 'no reaction.'
(k) 
Verified step by step guidance1
Identify the functional group present in the molecule. The given structure is a cyclohexanol derivative with a tertiary alcohol group.
For condition (iii) with SOCl₂ and NEt₃: Recognize that SOCl₂ (thionyl chloride) is used to convert alcohols into alkyl chlorides. The NEt₃ (triethylamine) acts as a base to neutralize the HCl formed during the reaction.
Predict the reaction mechanism for condition (iii): The hydroxyl group (OH) of the alcohol will be replaced by a chlorine atom, resulting in the formation of a tertiary alkyl chloride.
For condition (iv) with 1. TsCl, Et₃N 2. NaCN: Understand that TsCl (tosyl chloride) converts the alcohol into a tosylate, which is a good leaving group. Et₃N (triethylamine) acts as a base to facilitate this conversion.
Predict the reaction mechanism for condition (iv): The tosylate intermediate will undergo nucleophilic substitution with NaCN, resulting in the formation of a nitrile group, replacing the tosylate group.
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Key Concepts
Here are the essential concepts you must grasp in order to answer the question correctly.
Thionyl Chloride (SOCl₂) Reactivity
Thionyl chloride is a reagent commonly used in organic chemistry for converting alcohols into alkyl chlorides. The reaction proceeds through the formation of an intermediate that facilitates the substitution of the hydroxyl group with a chlorine atom. Understanding this mechanism is crucial for predicting the products of reactions involving SOCl₂.
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Triethylamine (NEt₃) as a Base
Triethylamine is a non-nucleophilic base often used in organic reactions to deprotonate acids or to neutralize generated acids. In the context of reactions with SOCl₂, NEt₃ helps to promote the formation of the desired alkyl chloride by removing protons and stabilizing the reaction environment. Recognizing its role is essential for understanding the overall reaction mechanism.
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TsCl and Nucleophilic Substitution
TsCl, or tosyl chloride, is used to convert alcohols into better leaving groups, facilitating nucleophilic substitution reactions. When combined with a base like Et₃N, it forms a tosylate intermediate, which can then react with nucleophiles such as NaCN. This concept is vital for predicting the products of the sequential reactions outlined in the question.
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01:47Nucleophiles and Electrophiles can react in Substitution Reactions.
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