(a)
Interpretation:
The given reactions are final steps in one industrial synthesis of vitamin A acetate.
The mechanism has to be proposed for the acid-catalyzed cyclization in step-1.
Concept Introduction:
The ring cyclization occurs when an acyclic molecule reacts with acid. by the abstraction of proton from the acid molecule, internal bond shifting occurs to form the cyclization product.
(b)
Interpretation:
The given reactions are final steps in one industrial synthesis of vitamin A acetate.
The reagents has to be given for the reaction involved in step-2.
(c)
Interpretation:
The given reactions are final steps in one industrial synthesis of vitamin A acetate.
The mechanism has to be proposed for the formation of phosphonium salt in step-4.
(d)
Interpretation:
The given reactions are final steps in one industrial synthesis of vitamin A acetate.
The reagents that are involved in the reaction of step-3 has to be proposed.
(e)
Interpretation:
The given reactions are final steps in one industrial synthesis of vitamin A acetate.
Wittig reaction of step-5 has to be shown.
Concept Introduction:
Wittig reaction:
The reaction of carbonyl compound with the ylide of phosphonium salt to give an
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Chapter 16 Solutions
Organic Chemistry
- (b) Answer ALL parts (i)-(iv) of this question. The scheme below outlines a synthesis of a vitamin A analogue. (i) Suggest reagents for the conversion of 1 into 2 and write a mechanism for this reaction; (ii) Suggest a reagent for the conversion of 3 into 4; (iii) Propose a mechanism for the conversion of 4 into 5; (iv) Suggest reagents for the conversion of 5 into 6 and provide a mechanism for this transformation. reagents? 2 reagents? PPH3; HBr ÓH 3 4 PPH3 Br reagents?arrow_forward(a) Draw the mechanism for the formation of both of the enols that can be formed from A (use acetic acid & AcOH as the source of the protons) (b) Draw the mechanism of reaction of this enol with bromine to give product Barrow_forwardPlease answer parts a,b,carrow_forward
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- Organic ChemistryChemistryISBN:9781305580350Author:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. FootePublisher:Cengage Learning