Concept explainers
(a)
Interpretation: The product formed by the photochemical electrocyclic ring opening or ring closure to the given compound is to be predicted. The process has to be labeled as conrotatory and disrotatory and the stereochemistry around stereogenic center and double bond is to be indicated.
Concept introduction: Electrocyclic reactions involve ring opening or ring closure in a conjugated polyene. According to Woodward-Hoffmann rules, the polyene containing even number of bonds in photochemical conditions undergoes reaction in disrotatory fashion and polyene containing odd number of bonds undergo reaction in conrotatory fashion.
(b)
Interpretation: The product formed by the photochemical electrocyclic ring opening or ring closure to the given compound is to be predicted. The process has to be labeled as conrotatory and disrotatory and the stereochemistry around stereogenic center and double bond is to be indicated.
Concept introduction: Electrocyclic reactions involve ring opening or ring closure in a conjugated polyene. According to Woodward-Hoffmann rules, the polyene containing even number of bonds in photochemical conditions undergoes reaction in disrotatory fashion and polyene containing odd number of bonds undergo reaction in conrotatory fashion.
Want to see the full answer?
Check out a sample textbook solutionChapter 27 Solutions
Organic Chemistry-Package(Custom)
- What product is formed when each compound undergoes thermal electrocyclic ring opening or ring closure? Label each process as conrotatory or disrotatory and clearly indicate the stereochemistry around tetrahedral stereogenic centers and double bonds. CeHs a. b. CeH5arrow_forwardDraw the products formed when attached alkene is treated with BH3 followed by H2O2, HO−. Include the stereochemistry at all stereogenic centersarrow_forwardDraw all of the substitution and elimination products formed from the given alkyl halide with each reagent: (a) CH3OH; (b) KOH. Indicate the stereochemistry around the stereogenic centers present in the products, as well as the mechanism by which each product is formed.arrow_forward
- Draw TWO tautomers of cyclohexa-2,4-dienone A. Place arrows between the three structures and indicate which is the most thermodynamically stable isomeric form and why. Aarrow_forwardDraw the products of attached reaction and indicate stereochemistry around stereogenic centers.arrow_forwardG.133.arrow_forward
- (a) Draw the products (including stereoisomers) formed when 2methylhex-2-ene is treated with HBr in the presence of peroxides. (b) Draw the products (including stereoisomers) formed when (S)-2,4dimethylhex-2-ene is treated with HBr and peroxides under similar conditions.arrow_forwardDraw the organic products formed when cyclopentene is treated withfollowing reagent. [1] OsO4 + NMO; [2] NaHSO3, H2Oarrow_forwardLl.58.arrow_forward
- Which alkene(s) would produce the indicated products under the conditions provided? ? Grubbs or Schrock Catalyst ? A) ō B) D) + C₂H4 (9) ERSEarrow_forwardRank the following compounds from lowest to highest heat of hydrogenation:arrow_forwardExplain the Stereochemistry of Carbonyl Reduction ?arrow_forward