(a)
Interpretation: The kind of sigmatropic rearrangement that occurs in each of the given reactions has to be given.
Concept introduction:
Pericyclic reactions are “ any concerted reaction in which bonds are formed or brocken in a cyclic transition state”. There is a single transition state from start to finish, in contrast to a stepwise reaction.
There are mainly three types of pericyclic reactions,
- 1) Electrocyclic reactions
- 2) Cycloaddition reactions
- 3) Sigmatropic reactions
In a sigmatropic reaction “ one new sigma-bond is formed as another breaks.”
Sigmatropic rearrangement reactions are named with digits. For example a [1, 3] sigmatropic rearrangement describe a reaction in which the residue migrates from position 1 to position 3.
(b)
Interpretation: Using arrows the electron rearrangement takes place in the given reactions has to be shown.
Concept introduction:
Pericyclic reactions are “ any concerted reaction in which bonds are formed or brocken in a cyclic transition state”. There is a single transition state from start to finish, in contrast to a stepwise reaction.
There are mainly three types of pericyclic reactions,
- 1) Electrocyclic reactions
- 2) Cycloaddition reactions
- 3) Sigmatropic reactions
In a sigmatropic reaction “ one new sigma-bond is formed as another breaks.”
Sigmatropic rearrangement reactions are named with digits. For example a [1, 3] sigmatropic rearrangement describe a reaction in which the residue migrates from position 1 to position 3.
![Check Mark](/static/check-mark.png)
Want to see the full answer?
Check out a sample textbook solution![Blurred answer](/static/blurred-answer.jpg)
Chapter 28 Solutions
CHEM 262 ORG CHEM EBOOK DIGITAL DELIVERY
- B 1 of 2 Additional problems in preparation to Midterm #1: 1.) How can the following compounds be prepared using Diels-Alder reaction: CH3 O CN (a) (b) CN CH3 2.) What is the missing reagent in the shown reaction? H3C + ? H3C H3C CN H3C ''CN (၁) H 3.) Write the products 1,2-addition and 1,4-addition of DBr to 1,3-cyclohexadiene. Remember, D is deuterium, a heavy isotope of hydrogen. It reacts exactly like hydrogen. 4.) In the shown reaction, which will be the kinetic product and which will be the thermodynamic product? H3C CI H3C HCI H3C + 5.) Which of the following molecules is aromatic? (a) (b) (c) H 6.) Which of the following molecules is aromatic? (a) (b) (c) 7.) Write the mechanism for the shown reaction. + Ха AICI 3 CI 8.) Suggest reagents that would convert benzene into the shown compounds. CI NO2 -8-6-6-8-a (a) (b) (c) (d) (e) (a) SO3H Brarrow_forwardThe number of 2sp^2 hybridized atoms in is: A. 8; B. 6; C.4; D.2; E.0;arrow_forwardThe highest boiling compound from among the following isA. 2-methylheptane; B. 3-methylheptane; C. 2,2-dimethylhexane;D. octane; E. 2,2,3-trimethylpentanearrow_forward
- Which of the following features are found in the most stable structure ofCH5NO that does not have a CO bond?w. a π bond, x. two NH bonds, y. one OH bond, z. 3 lone pairsA. w, x; B. x, y; C. y, z; D. x, y, z; E. all of them.arrow_forwardWhich one of the following functional groups is not present in thecompound shownA. amine; B. aldehyde, C. ether; D. amide. E. ketonearrow_forwardWhich of the following formulas correspond to at least one compound inwhich resonance is important?w. C2H5N x. C3H5Br; y. C3H4; z. C4H6.A. w, x, y; B. x, y, z; C. w, x, z; D. w, y, z; E. all of themarrow_forward
- Predict the product(s) that are formed after each step for reactions 1-4. In each case, consider formation of any chiral center(s) and draw all expected stereoisomers. 1) OH 1) HBr (SN2) 2) NaOH, heat 3) BH3, THF 4) H2O2, NaOH 2) OH 1) SOCI 2, py 2) NaOEt 3) Br2, H₂O 3) OH 1) H2SO4 conc. 2) HBr, ROOR 3) KOtBu 4) OH 1) TsCl, py 2) NaOEt 3) 03 4) DMSarrow_forwardWhich of the following rings has the least strain in its most stableconformation?A. Cyclobutane; B. Cyclopentane; C. Cyclohexane; D. Cycloheptane;E. Cyclooctanearrow_forwardThe number of different carbon skeletons that have a main chain of 9carbons and an ethyl branch isA 3; B. 4; C. 5; D. 6; E. 7arrow_forward
- Q5: Classify the following pair of molecules as constitutional isomers, enantiomers, diastereomers, the same molecule, or completely different molecules. Br O CI Br OH OH 111 Br .!!!/Br F OH and ...m Br Br OH CI Br OH ་་་་་" ། ་arrow_forwardConsidering only rotation around the 1-2 bond, how many differentstaggered conformations are there of 1,2-dibromo-1,2-dichloropropane?A: 2; B. 3; C. 4; D. 6; E. more than 6.arrow_forwardcan you help me solve thisarrow_forward
- Organic Chemistry: A Guided InquiryChemistryISBN:9780618974122Author:Andrei StraumanisPublisher:Cengage Learning
![Text book image](https://www.bartleby.com/isbn_cover_images/9780618974122/9780618974122_smallCoverImage.gif)