Hydrocarbons Questions and Answers

At approximately what temperature does the solubility of sodium chloride NaCl match the solubility of potassium chlorate KC1O3 1 63 C 2 53 C 3 83 C 4 33 C 100 unprece of water at 40 C the solution can be correctly

True False The major diastereomer produced in this reaction is A HE True False DMDO A THE H B www

Compare the two reactions A and B shown below Check all the statements that are TRUE regarding the epoxide products B DMDO X 8 1 i The epoxide from A is not optically active The epoxide from A is optically active The epoxide from A is enantiomerically enriched The epoxide from B is racemic The epoxide from B is enantiomerically enriched The epoxide from B is optically active The epoxide from A is racemic The epoxide from B is not optically active go

Write the synthesis of the following compound Br Br T

Sup MAUTIFU 2 Which aromatic oxalate esters produced the brightest glow with rubrene as the acceptor Which glow lasted longest How do the substituents electron donating vs electron withdrawing affect the efficiency of the chemiluminescence reaction

8 1 Draw the structural formula for each of the following a 5 chloro 4 methyl 2 hexanol 2 3 dimethylcyclopentanol c 5 5 diethyl 1 heptanol b d 2 ethyl 4 isopropylcyclohexanol e 4 ethylphenol f 2 nitrophenol g cyclopropyl methyl ether h isopropyl propyl ether

I write the synthesis of the following compound IV F V

What is the dominant mechanism operative in the reaction below O SN2 OSN1 O no reaction occurs OE2 OH O E1 H SO4 heat mechanism

What reagents are the best choice for the transformation below O 1 PBr3 pyridine 2 NaCN O 1 HBr OH 2 NaCN O HCN O 1 TsCl pyridine 2 NaCN CN

Predict the major product of the following reaction the CH3 enantiomer A OA OB OC OH C H3O OH CH3 enantiomer B OH tym C D OH CH3

Which of the given reaction schemes would produce the molecule shown below CH8 01 11 O III OI and II Ou Lu HBr ROOR 11 Br HBr HBr ROOR

Which of the following is the most stable isomer CH4 COI I SO II O III IV

Name the following compound CH4 O 2 isopropyl 3 6 dimethylbicyclo 3 2 2 nonane O 2 isopropyl 3 8 dimethylbicyclo 3 2 2 nonane O 3 isopropyl 2 8 dimethylbicyclo 3 2 2 nonane O 6 isopropyl 7 9 dimethylbicyclo 3 2 2 nonane O 7 isopropyl 6 8 dimethylbicyclo 3 2 2 nonane

13 31 Tetrahydrofuran THF can be formed by treating 1 4 butanediol with sulfuric acid Propose a mechanism for this transformation OH H SO HO 1 4 Butanediol Tetraburraturen

13 34 Identify the reagents necessary to accomplish each of the fol lowing transformations b 10

The synthesis above used bromoethane but acetylene is the only allowed source of carbon atoms Using the reagents given identify a synthetic route for the production of bromoethane from acetylene H H The transformation above can be performed with some reagent or combination of the reagents listed below Give the necessary reagent s in the correct order as a string of letters without spaces or punctuation such as EBF If there is more than one correct solution provide just one answer A B H Lindlar s cat D NaNH Br E C H Pt F

A 10 0 g sample of a compound is found to contain 1 00 g carbon 0 840 g hydrogen and 8 16 g chlorine What is the compound s percent composition Select the correct answer below O 19 4 carbon 31 9 hydrogen 48 7 chlorine O 51 0 carbon 22 7 hydrogen 26 3 chlorine 1 00 carbon 0 840 hydrogen 8 16 chlorine 10 0 carbon 8 40 hydrogen 81 6 chlorine Ih

Predict the major product of the following reaction BH r 01 11 O III CON 2006 OH hove H O H OH III IV

1 Hexyne is treated with sodium hydride followed by bromoethane Lindlar hydrogenation of the resulting product affords what final product Z 3 octene Z 2 octene E 3 octene E 2 octene H 1 NaH 2 CH3CH Br Lindlar s catalyst

OA OB XX 4 OC Predict the final product of this 3 steps reaction OD M t N 3 Na NFL g hard

a b O d e f OH OH 3 Complete the following reaction scheme Give all product s and indicat major or minor and any relevant stereochemistry 60 points 4 points each Br Br dil HCI NaOEx heat H heat NaCN DMF HBr 8 H SO4 H PO4 heat

c What type of mechanism step s occur s in the second step LLG neve attack 2 Draw the product s of the following reactions a b C Br Br BrB Br 5 Bro Q BV oferererer Br OY Por Br W Br BY comentar B1 or or twor Br

1c Explain what an nucleophile is and identify which is the nucleophile in the following reaction H Hydronium ion Cyclohexene A nucleophile is The structure that is a nucleophile is 1d Explain what an electrophile is and identify the electrophile in the above 1c reaction An electrophile is The structure that is an electrophile i

Please provide the reagent s needed to complete the reactions PROVIDE REAGENTS G i MOH ye 0 ini on vyh OH now in

owing reactions indicating stereochemistry where appropriate If no reaction is anticipated write no reaction

HCN Lewis Structure with dipoles CS Lewis Structure with dipoles HC H O Lewis Structure with dipoles the atoms are bonded in the following order C C O O H Molecular Geometry Number of electron domains Bond Angle s Central Atom s Hybridization This molecule is polar nonpolar Molecular Geometry Number of electron domains Bond Angle s Central Atom s Hybridization This molecule is polar nonpolar Molecular Geometry Number of electron domains Bond Angle s Central Atom s Hybridization This molecule is polar nonpolar

What are the products formed when an ethyl radical abstracts a bromine atom from Br2 O O O O C CH CH and HBr CH CH Br and H CH CH Br and Br CH CH Br and H

3 Complete the following reaction scheme Give all product s and indicate major or minor and any relevant stereochemistry 60 points 4 points each h 0 1 k H C 1 BH THE 2 H O OH 1 Hg OAC H O 2 NaBH KMnO4 NaOH Cold P4 C MO

6 Draw two chair conformations chair flips of the structure given below and circle the more stable chair conformation 10 pts OH

Hydration of alkenes produced alcohols Hydration of alkynes produces an enol since you have an extra pi bond The enol tautomerizes to the keto form aldehyde or ketone The equilibrium is shifted to the keto form Keto enol tautomerism can be acid or base catalyzed depending on the conditions Write the curved arrow mechanism for the acid catalyzed keto enol tautomerism below Show all bonds and lone pairs involved in reactivity a The double bond acts as a Lewis base and donates a pair of electron to the proton from hydronium ion forming the more stable carbocation b The carbocation is stabilized by resonance of the lone pair of oxygen forming oxonium ion c Water deprotonates the oxonium ion yielding the ketone and recovering the catalyst H H3O

4 Write a complete stepwise mechanism for any TWO of the following You need to use curved arrows to show electron flow 10 points HCI X Q9 Heat NaOEt hant major minor EtOH NaBr H O

MeO C d OH OH CO Me CI H O H CI H CO Me CO Me

Write the curved arrow mechanism for each of the following a b c Br HOCH 3 OCH3 Br 1 BH 3 THF 2 H O2 NaOH H O 1 Hg OAc H O 2 NaBH4 enantiomer OH OH Reaction mechanism for reaction 2 is not clear Just change the mercury acetate in the compound for H

2 CsH14 19 O2 12 COz 14 H2O Hexane C6H14 burns in a combustion reaction How many moles of oxygen are needed for the complete combustion of 9 88 X 10 1 molecules of hexane O 3 49 mol O 0 156 mol O4 99 mol O 0 0017 mol

How many hydrogen atoms are there in heptane the linear hydrocarbon with seven carbon atoms a 20 O b 16 c 22 d 18

Treatment with O3 followed by dimethyl sulfide DMS converts a trans disubstituted alkene into a n primary alcohol and aldehyde allylic alcohol and ketone secondary alcohol and carbon dioxide tertiary alcohol and carboxylic acid aldehyde and aldehyde ketone and ketone aldehyde and carbon dioxide 4

The reaction of methylpropene with HBr in ether gives one of the two products below as the major product Answer the following question s about th Product t HBr ether Br Product A would be formed via a primary carbocation Br Product B

Five liquids are shown below Which one would have the highest viscosity H H H H H H H H 1 H C C C C C c c c H H H II H O C C 0 H H H III HH IV H O H HO H H O C C C 0 H H H H HHHHHH V H C C C C C C H 1 1 1 1

Which 4 step process would convert the reactant to the product Excess reagent is implied if needed Hint Attempt this question towards the end of the exam so flag it if you get it in the beginning 1 Br dilute sulfuric acid 2 HBr t BUOK 3 HBr ROOR 1 03 2 water Me in NH3 1 4 H2 Lindlar NaOEt

OH Select one OEA O EA O EA O EA HCI H O CI reaction ordinate reaction ordinate reaction ordinate

The numbered elementary steps below each belongs each step with its type I E IV Br Br heat Br Br Choose Choose propagation step Br I HBr

Match the following items Drag and drop options on the right hand side to reorder and match with items on the left Reordering may cause items on the right hand side to swap positions Step 1 Step 2 Step 3 CH3CH CH CH Br Na NH3 NaNH2 NH3 2 equivalents Cl 2 equivalents HBr

If a scientist combined 130 81g of reactant X from the chemical equation below with 124 85g of reactant Y what will the total mass of the products be Assume the reactants were completely used up during the reaction and report your answer without units Reaction X Y Z H

Match the reagent to the steps for the synthesis of 2 hexanone from acetylene Drag and drop options on the right hand side to reorder and match with items on the left Reordering may cause items on the right hand side to swap positions Step 1 Step 2 Step 3 Step 4 Step 5 CH3CH CH Br NaNHz NH3 NaNHz NH3 CH31 03 H O KMnO4 H O OH H O H SO4 HgSO4 III

16 Which reaction below gives a single enantiomer of an optically active chiral product 0 H CH3 CH3COOH A B C D H CH3 CH3 CH3 HBr peroxides 1 BH3 THF 2 H O2 NaOH HBr

Predict the major product of this organic reaction CH3 CH CH CH3 H2O Specifically in the drawing area below draw the condensed structure of the major product If there is no reaction check the No reaction box under the drawing area C C X G

If the compound below were reacted with concentrated sulfuric acid which major product would be obtained HO Select one

How many given ligands can act as electron donor and T acceptor in complexes CH CH2 NH3 PF3 C6H6 C5H5 H O

If the compound below were reacted with 1 excess H and Pd C which major product would be obtained Select one O X 10

the compound below were reacted with Br2 H O which major product would be obtained a Select one Ait Br Br OH Br OH OH H Br OH