Reaction 3. Electrophilic addition of halogens (X₂) to alkenes.X+RX₂RX = Br, ClReagents and conditionsMechanistic detailselectrophilic additionBr2, Cl₂ in CCl4 (or AcOH)room temperaturebromonium or chloronium ion intermediates• anti additionReaction 25. Elimination reaction to form carbon-carbon double bonds.R2XR2BeR4RC-CR4(-HX)HRIR3R3X-leaving group (for example: Cl, Br, I, Tos)B = base (for example: HO, H₂N, t-Buo,C1, H₂O, RNH₂)Reagents and conditionsMechanistic detailsEl mechanism for tertiary or secondary allylic or benzylicsubstrates: the leaving group departs in a unimolecular rate-limiting step, generating the carbocation, which in the secondstep is deprotonated (with base) on the carbon adjacent to thecationc center, yielding the olefin; carbocation rearrangementsmay competevariety of conditions andsolventsusually strong bases favorE2 mechanismE2 mechanism favored by strong bases: the base removes aproton from the carbon adjacent to one bearing the leaving groupin a one-step bimolecular reaction that requires periplanarorientation of the hydrogen and the leaving group (anti-periplanar preferred)competition with substitution reactions (S₁1and SN2) oftenobservedUsually the most substituted olefin is the major product(Zaitsev's rule) (E) -1-2- Diphenylethene reacts with Br2 /CCI 4 (see reaction) the reaction product is obtained (A) is astereoisomer with 2 chiral optically inactive carbons that then reacts with KOH / ethanol (see reaction) that producesan intermediate (B) [C₁4H₁1 Brl that by continuing to react with KOH and heating to 190 degrees Celsius,compound (D) C14H10 is obtaineda) Write the general reaction of this synthesis with the structures of the initial alkene of A, B and Db) Give the reaction mechanism to obtain Ac) Indicate for the absolute configuration of each C* and the IUPAC name of the compoundd) Give the IUPAC and common name of the obtained product D

Answered: Image /qna-images/answer/6497f123-5ed2-4519-9a0f-a10d4e3e755b.jpg

(E)-1-2- Diphenylethene reacts with Br 2 /CCI4 (see reaction) the reaction product is obtained (A) is a stereoisomer with 2 chiral optically inactive carbons that then reacts with KOH / ethanol (see reaction) that produces an intermediate (B) [C₁4H₁1 Brl that by continuing to react with KOH and heating to 190 degrees Celsius, compound (D) C14H10 is obtained a) Write the general reaction of this synthesis with the structures of the initial alkene of A, B and D b) Give the reaction mechanism to obtain A c) Indicate for the absolute configuration of each C* and the IUPAC name of the compound d) Give the IUPAC and common name of the obtained product D

(E)-1-2- Diphenylethene reacts with Br 2 /CCI4 (see reaction) the reaction product is obtained (A) is a stereoisomer with 2 chiral optically inactive carbons that then reacts with KOH / ethanol (see reaction) that produces an intermediate (B) [C₁4H₁1 Brl that by continuing to react with KOH and heating to 190 degrees Celsius, compound (D) C14H10 is obtained a) Write the general reaction of this synthesis with the structures of the initial alkene of A, B and D b) Give the reaction mechanism to obtain A c) Indicate for the absolute configuration of each C* and the IUPAC name of the compound d) Give the IUPAC and common name of the obtained product D

Organic Chemistry: A Guided Inquiry

2nd Edition

ISBN:9780618974122

Author:Andrei Straumanis

Publisher:Andrei Straumanis

Chapter14: Elimination

Section: Chapter Questions

Problem 40CTQ

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