Concept explainers
Interpretation:
A step by step mechanism for both the transformation of Robinson annulation sequence is to be provided, and the acidity of
Concept introduction:
Electrophiles are electron deficient species that have positive or partially positive charge. Lewis acids are electrophiles that accept electron pair.
Nucleophiles are electron rich species that have negative or partially negative charge. Lewis bases are nucleophiles that donate electron pair.
Free radical is an atom, molecule, or ion that has an unpaired electron that makes it highly chemically reactive.
Substitution reaction: A reaction in which one of the hydrogen atoms of a hydrocarbon or a
Elimination reaction: A reaction in which two substituent groups are detached and a double bond is formed is called elimination reaction.
Addition reaction: It is the reaction in which unsaturated bonds are converted to saturated molecules by the addition of molecules.
A base removes acidic hydrogen and forms an enolate.
The enolate adds to the
A carbon–carbon bond formation occurs by aldol addition and aldol condensation reaction.
An aldol reaction takes place in a protic solvent with a base.
An aldol reaction takes place by acid catalysis, and direct dehydration of
A
A chemical reaction that is catalyzed by a base is called base catalyzed reaction.
Aldol reaction is preferred in basic condition over acidic condition, as after the aldol condensation, acid catalysis promotes the reaction further.
In Robinson annulation reaction, Michael addition, followed by simple aldol condensation, takes place.
The Robinson annulation reaction is used to form one ring on to another.
A resonance structure which stabilize the conjugate base also increases the acidity.
The rules for drawing resonance structures are as:
Only nonbonding electron pairs and pi electrons can participate in conjugation in the formation of various resonating structures.
The single bonds present in the molecule do not break or form in the resonance structures.
The placement of atoms present in the molecule remains fixed.
The octet of all atoms is completely filled.
More the number of resonance structures indicate higher stability of a compound.
Want to see the full answer?
Check out a sample textbook solutionChapter 19 Solutions
ORGANIC CHEMISTRY (LL) W/WILEYPLUS NEXT
- A pdf file of your hand drawn, stepwise mechanisms for the reactions. For each reaction in the assignment, you must write each mechanism three times (there are 10 reactions, so 30 mechanisms). (A) do the work on a tablet and save as a pdf., it is expected to write each mechanism out and NOT copy and paste the mechanism after writing it just once. Everything should be drawn out stepwise and every bond that is formed and broken in the process of the reaction, and is expected to see all relevant lone pair electrons and curved arrows. Aldol: NaOH HO H Δ NaOH Δarrow_forwardNonearrow_forwardDraw structures corresponding to the following names and give IUPAC names for the following compounds: (8 Point) a) b) c) CH3 CH2CH3 CH3CHCH2CH2CH CH3 C=C H3C H H2C=C=CHCH3 d) CI e) (3E,5Z)-2,6-Dimethyl-1,3,5,7-octatetraene f) (Z)-4-bromo-3-methyl-3-penten-1-yne g) cis-1-Bromo-2-ethylcyclopentane h) (5R)-4,4,5-trichloro-3,3-dimethyldecanearrow_forward
- Draw a Newman projection from carbon 3 to carbon 2 in the highest energy conformation for the following molecule. What is this conformation called? What kind of strain is present? Brarrow_forwardWhich of the following dienophiles is most reactive in a Diels-Alder reaction: Please explain why the correct answer to this question is option 5. Please provide a detailed explanation.arrow_forwardWhich of the following would you expect to be aromatic? Please provide a detailed explanation.arrow_forward
- Organic ChemistryChemistryISBN:9781305580350Author:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. FootePublisher:Cengage Learning