Interpretation:
The short sequences of reactions that would be appropriate for the given transformations, using the indicated starting material are to be written.
Concept introduction:
Friedel Craft acylation is an electrophilic
Grignard reaction is a reaction in which aryl or
The molecule,
Dess Martin periodinane (DMP) is a reagent which is used for the oxidation of primary alcohols to
The Diels–Alder reaction is a
Answer to Problem 42P
Solution:
a) Short sequences of reactions that are appropriate for the transformation of
b) Short sequences of reactions for the transformation of the given compounds are shown below.
c) Short sequences of reactions for the transformation of the given compound from
d) Short sequences of reactions for the transformation of the given compounds are shown below.
e) Short sequences of reactions that are appropriate for the transformation of the given compound from
f) Short sequences of reactions that are appropriate for the transformation of the given compounds are shown below.
g) Short sequences of reactions that are appropriate for the transformation of the given compounds are shown below.
Explanation of Solution
a) Short sequences of reactions that would be appropriate for the transformation of
Treatment of
The tertiary alcohol so obtained undergoes dehydration with conc.
Reduction of the alkene with
b) Short sequences of reactions that would be appropriate for the transformation of the compounds given below have to be decribed.
Treatment of cyclopentyl(phenyl) methanone with griginard reagent
The tertiary alcohol, upon dehydration with conc.
c) The structure of the compound which has to be synthesized from
The reaction of
The griginard reagent formed reacts with
The alcohol formed reacts with dess martin periodinane to form ketone as shown in the reaction below.
The ketone reacts with Wittig reagent
d) Short sequences of reactions that would be appropriate for the transformation of the compounds given below have to be described.
Oxidation of the given alcohol using pyridinium dichromate (PDC) in
Protection of acidic proton of is done by reaction of the aldehyde with
Reaction of the aldehyde with the griginard reagent, hexylmagnesium chloride, produces an alcohol as shown in the reaction below.
Alcohols react with martin dess periodinane to form ketone as shown below.
Terminal alkynes are converted to ketones by reaction with
e) The structure of the compound which has to be synthesized from
In the reduction of
The hydroxyl group of the alcohol is a poor leaving group and therefore, it is reacted with
The
f) Short sequences of reactions that would be appropriate for the transformation of the compounds given below have to be decribed.
Reduction of the ketone shown above with zinc-amalgam produces a hydrocarbon in Clemmenson’s reduction as shown in the reaction below.
Friedal Crafts acylation of the aromatic ring obtained with
g) Short sequences of reactions that would be appropriate for the transformation of the compounds given below have to be decribed.
Treatment of the reactant with griginard reagent
The tertiary alcohol so obtained undergoes dehydration with conc.
Diels-Alder reaction of the diene with the dienophile produces the desired product as shown in the reaction below.
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Chapter 18 Solutions
ORGANIC CHEMISTRY (LOOSELEAF)-PACKAGE
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