University:
Rutgers University Newark
Course:
CHEM 335 | Organic Chemistry
Academic year:

2024
Views:

199

Pages:

28
Author:

Mahitab S.

I.gr Toy OH Bjp B Br N NEBR 123456 1234 z's's NEY ME Ng Matt Me CHAPTER of Brz Addition - = * CHEAT SHEET 7 $ Clz Br - bridge anti - intermediate, HE addition . → mechanism E N ÷÷Ii÷ - → Bridge ¥+01 → rÉÉ +13%-0 I E Addition =\ of HBR HBr_ ↳ mechanism : =it-P3r N =gBr carbocation int → * É3r3 E . → ¥ Internal Alkyne - = - → [ HYDROBORATION ] Ketone É OH tg É 2) Hzoz, NaOH tautomerism Acid - = Catalyzed Hydration - Terminal + Alkyne ÷n:# i Hzo → É Hgsoy in É É tautomerism H Aldehyde %÷÷÷E OH Keeton ix. SYNTHESIS ① alkyne → →m¥Éwot ×¥É Ñ¥¥Éndiar Hzsou ② ☒ alkyne , H2O H⑦ %I¥¥÷ñar / ¥¥pz,Na° ← " =L - - y terminal - anti - mark Hydroborination - B Br % ⇐→ 4m butyric - ÷Éy :c - trans . ↳ 4- Fyne qBr ±Br f ten cis gcs . . 4 6 halo - halogen É¥¥É alkanet - = ' brtyme hexyne organic solvent transprodvcIEEF-mhe.r.ir hexyne hexene Br tr * ten For cisprodvc.TO Lz -1 Lindlar th . & To Br r + en cis alkene E4C / i 6C Nantz more Et Br ✓ stable end - ② ⇐ ¥¥÷± H Tmajor Hou product Hao # of 2 → (E) = g - p trans = No me - Br • E 2- T pentene # - where doublet bond - C y is g Et ' - Br [ = - Na NHS (e) N a Chem 335 PLR Chapter 7 PSet REDUCTION 1. Identify reagents that you could use to achieve each of the following transformations. ] Hz ( Lidar ) Na NH} Ll) Na #→ Ntbll) Hz Pt or ② alkene - Is - trans ] trans alkene alkene ] alkane transition metal . 2. Propose an efficient synthesis for each of the following transformations. Multistep Synthesis Starting with 1-butyne, how would you prepare the ketone product? How would you prepare (E)-2-pentene from ethyne? How would you prepare 3,3-dibromohexane from ethyne? Chem 335 PLR Chapter 7-2 PSet For each of the following transformations, predict the major product and draw a mechanism for its formation: Predict the major product(s) expected for each of the following reactions: Hydration of Alkynes Acid-Catalyzed Hydration of Alkynes Alkynes are observed to undergo acid-catalyzed hydration. The enol and ketone are tautomers, which are constitutional isomers that rapidly interconvert via the migration of a proton. The interconversion between an enol and a ketone is called keto-enol tautomerization. Tautomerization is an equilibrium process, which means that the equilibrium will establish specific concentrations for both the enol and the ketone. Generally, the ketone is highly favored. Note: Do not to confuse tautomers with resonance structures. The following enols cannot be isolated. They rapidly tautomerize to produce ketones. In each case, draw the expected ketone, formed under acid-catalyzed conditions (H O ). + 3 Draw the major product(s) expected when each of the following alkynes is treated with aqueous acid in the presence of mercuric sulfate (HgSO ): 4 Hydroboration-Oxidation of Alkynes Draw the major product for each of the following reactions: Identify reagents that you could use to achieve each of the following transformations: Organic Chemistry Review ing go EE Iii 0 gg A Basics of Synthesis • ALWAYS count the number of carbons in your product compared to your starting material • Identify the different functional groups in your product/starting material • Identify the type of substrate you have for each step • Identify the kind of reactions you’ll need, then think of regioselectivity/stereoselectivity • Check your work!!! Propose a synthesis of (3-ethoxypropyl)cyclohexane from allylcyclohexane without using any reagents that would form radical intermediates. Propose a synthesis of 4-methyl-pentan-2-one using ONLY acetylene and 2-methyl-propane as your sources of carbon molecules. Propose a synthesis of isophthalic acid from 1,3-dimethyl-benzene using any reagents you’ve learned. Propose a synthesis of 2-hydroxy-2-methylbutanal from neopentane (2-dimethyl-propane). +enantiomer +enantiomer Propose a synthesis of 1,5-pentanediol from cyclopentene.