Concept explainers
Interpretation:
It should be explained that why two different products are formed from disrotatory ring closure of (2E, 4Z, 6Z)-octatriene, but only one product is formed from disrotatory ring closure of (2E, 4Z, 6E)-octatriene.
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 an electrocyclic reaction “one new sigma- bond is formed or brocken.”
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,
Enantiomers are a type of stereoisomers that have the same molecular formula and constitutions around the atom but differ in their spatial arrangement of groups around the atom.
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Chapter 28 Solutions
Organic Chemistry
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- Part A What is the major product formed when the following compound undergo an E1 reaction? CH, CH CH;CH,C–CHCH;CH3 Br for bonds ond chargee) Atoms gnd Terarrow_forwardDraw the keto and enol forms of 3,3-dimethylbutan-2-one, circle the more stable tautomer, and propose a mechanism for the conversion of one tautomer to the other in acidic conditions.arrow_forwardSelect the reagents that will allow the following transformation to occur. ? 1) О3 2) DMS OsO4 H2O2 mCPBA 1) ВН3 2)Н2О2, NaOH ОН ОН + enantiomerarrow_forward
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