(a)
Interpretation: If the reaction is proceeding under thermal conditions then the ring closure of the given compound
Concept introduction:
Woodward –Hoffmann rules are the set of rules used to vindicate or predict certain aspects of the stereo chemical outcome and activation energy of pericyclic reactions.
Woodward – Hoffmann rules for Electrocyclic reactions are listed below
(b)
Interpretation: The configuration of product has to be predicted.
Woodward –Hoffmann rules are the set of rules used to vindicate or predict certain aspects of the stereo chemical outcome and activation energy of pericyclic reactions.
Woodward – Hoffmann rules for Electrocyclic reactions are listed below
Woodward – Hoffmann rules for the configuration of electrocyclic reactions are,
(c)
Interpretation: If the reaction is proceeding under photochemical conditions then the ring closure of the given compound
Woodward –Hoffmann rules are the set of rules used to vindicate or predict certain aspects of the stereo chemical outcome and activation energy of pericyclic reactions.
Woodward – Hoffmann rules for Electrocyclic reactions are listed below
(d)
Interpretation: The configuration of the product has to be predicted.
Concept introduction:
Woodward –Hoffmann rules are the set of rules used to vindicate or predict certain aspects of the stereo chemical outcome and activation energy of pericyclic reactions.
Woodward – Hoffmann rules for Electrocyclic reactions are listed below
Woodward – Hoffmann rules for the configuration of electrocyclic reactions are,
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Organic Chemistry (8th Edition)
- 10. Which of these describe a set of enantiomers? a. (2R,3R)-2-bromo-3-chloropentane and (2S,3S)-3-bromo-2-chloropentane b. (2R,3R)-2-bromo-3-chlorpentane and (2R,3S)-2-bromo-3-chloropentane c. (2S,3S)-2-bromo-3-chloropentane and (2S,3R)-2-bromo-3-chloropentane d. (2S,3S)-2-bromo-3-chloropentane and (2R,3R)-2-bromo-3-chloropentane e. None of these.arrow_forwardWhich stereoisomer of 3-hexene forms (3S,4S)-4-bromo-3-hexanol and (3R,4R)-4-bromo-3-hexanol when it reacts with Br2 and H2O?arrow_forwardA chemist allows some pure (2S,3R)-3-bromo-2,3-diphenylpentane to react with a solution of sodium ethoxide(NaOCH2 CH3) in ethanol. The products are two alkenes: A (cis-trans mixture) and B, a single pure isomer. Under the same conditions, the reaction of (2S,3S)-3-bromo-2,3-diphenylpentane gives two alkenes, A (cis-trans mixture) and C. Upon catalytic hydrogenation, all three of these alkenes (A, B, and C) give 2,3-diphenylpentane. Determine the structures of A, B, and C; give equations for their formation; and explain the stereospecificity of these reactions.arrow_forward
- 6. When optically pure (R)-2-bromobutane is heated with water, butan-2-ol (CH3CHOHCH2CH3) is the product. The reaction forms twice as much (S)-butan-2-ol as (R)-butan-2-ol. Calculate the ee and the specific rotation expected for the product.arrow_forwardDehydrohalogenation of vinyl halides is essentially an E2 process. A stereochemical study revealed that (Z)-2-chloro-2-butendioic acid reacted 50 times faster than its E stereoisomer. 1. Na+ NH2 HO,C-c=c-co,H 2. H,о For the reaction below: Br 1. Na* NH2 2. H3O* H Ph a Draw the structure of the major organic product.arrow_forwardDraw the product of each electrocyclic reaction.a. the thermal electrocyclic ring closure of (2E,4Z,6Z)-nona-2,4,6-trieneb. the photochemical electrocyclic ring closure of (2E,4Z,6Z)-nona-2,4,6-trienec. the thermal electrocyclic ring opening of cis-5-ethyl-6-methylcyclohexa-1,3-diened. the photochemical electrocyclic ring opening of trans-5-ethyl-6-methylcyclohexa-1,3- dienearrow_forward
- 6. What happens if butadiene-1,3 is treated with: a) Br2, b) HCl. 7. Write the following sequence of reactions: Na H3C-CI Cl,/UV A KOHalc KMNO4 C В D t°C 20°Carrow_forward2. Show the structures of the carbocation intermediates you would expect in the following reactions: CH3 CH3 CH3CH2C=CHCHCH3 (a) (b) -CHCH3 HI ? HBr ? 3. What product would you expect to obtain from addition of Br2 to 1,2-dimethyl- cyclohexene? Show the cis or trans stereochemistry of the product.arrow_forward1. determine the type of pericyclic reaction (sigmatropic, electrocyclic, cycloaddition) 2. draw the mechanism for the reaction using curved arrows, and then use molecular orbital theory to evaluate the appropriate HOMO-LUMO interactions 3. determine the stereochemistry of the product, if necessary CHOOSE TWO OUT OF THE THREE PROBLEMS TO COMPLETE heat A RO, LOR КН, THF RO, в -OH ROH ...OR' 2. МеОн, Н,о OR' heatarrow_forward
- Which of the molecules A through D shown below will give mixtures of enantiomers upon reaction with HCI? C&H5 CeHs A B C D O 1, Molecules B and C. O 2, Molecules A and B. O 3, Molecules C and D. 0 4. Molecules A and C.arrow_forward7. Show how you would synthesize each compound using methylenecyclohexane as your starting material. If a chiral product is shown, assume that it is part of a racemic mixture. methylenecyclohexane Br `OH HO а. b. с. d. OCH3 ОН `CI ОН е. f. g. h.arrow_forwardthe product obtained from the reaction of 1,3-butadiene with cis-1,2-dichloroethene O because it is a meso compound O because is has no asymmetric centers O because it is a racemic mixture O because it has a point of symmetry the product obtained from the reaction of 1,3-butadiene with trans-1,2-dichloroethene O because it is a meso compound Obecause is has no asymmetric centers Obecause it is a racemic mixture because it has a point of symmetryarrow_forward
- Organic ChemistryChemistryISBN:9781305580350Author:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. FootePublisher:Cengage Learning