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1) 7-oxa[2.2.1]hept-2-ene

Draw the starting compounds for the preparation of 7-oxa[2.2.1]hept-2-ene by the Diels-Alder reaction.



(Enciphered hint 1: Ejfmt-Bmefs sfbdujpo.)

2) Phosgene with ethylamine

Fill the following scheme:



(Enciphered hint 1: Ovdmfpqijmjd tvctujuvujpo ublft qmbdf gpsnjoh bo vsfb. Uif bnjof fydftt jt ofdfttbsz up ofvusbmjaf gpsnjoh IDm.)

3) Diphenylketone and Beckmann rearangement

Diphenylketone reacts with hydroxylamine and the formed compound is treated under acid-catalyzed conditions. Draw the products of both reactions.



(Enciphered hint 1: Beejujpo pg izespyzmbnjof up dbscpozm hspvq.)



(Enciphered hint 1: Cfdlnboo sfbssbohfnfou. Bnjef jt gpsnfe.)

4) Dichlorobenzene with nitric acid and then with ammonia

What product is formed by the reaction of 1,3-dichlorobenzene with a mixture of nitric and sulfuric acids (consider the major product), and then with ammonia in ethylene glycol?



(Enciphered hint 1: Bmtp tufsjd ijoesbodf qmbzt spmf evsjoh fmfdupqijmjd tvctujuvujpo.)


(Enciphered hint 1: B njyuvsf pg uxp qspevdut jt gpsnfe.)

5) Reductive amination 4

Draw the starting compounds which produce the tertiary amine shown bellow on reductive amination.



(Enciphered hint 1: B dbscpozm dpnqpvoe boe bo bnjof bsf offefe.)

6) 1-Bromobutan-2-ol with sodium hydroxide

Draw the product of the following reaction.



(Enciphered hint 1: Jousbnpmfdvmbs ovdmfpqijmjd tvctujuvujpo.)

7) Preparation of dibromoderivative

Draw the starting alkene suitable for the preparation of dibromoderivative using bromine.



(Enciphered hint 1: Bouj-beejujpo pg cspnjof.)

8) Preparation of 1,2-dimethylcyclohex-1-ene

Draw the starting compounds for the preparation of 1,2-dimethylcyclohex-1-ene by the Diels-Alder reaction.



(Enciphered hint 1: Esbx uif tubsujoh ejfof boe ejfopqijmf (bmlfof).)

9) Synthesis of D-arabinaric acid

Which pentose gives the same aldaric acid as D-arabinose on oxidation with nitric acid? Draw the three-dimensional structure of its open-form.



(Enciphered hint 1: Ju jt bopuifs E-qfouptf.)
(Enciphered hint 2: E-Mzyptf.)

10) Kiliani-Fischer synthesis 2

What aldopentose would give a mixture of D-galactose and D-talose on Kiliani-Fischer synthesis? Draw the three-dimensional structure of its open-chain form.



(Enciphered hint 1: Uif Ljmjboj-Gjtdifs tzouiftjt sftvmut jo uif dibjo mfohuifojoh cz pof dbscpo bupn. Uif -DIP hspvq cfdpnft uif D2 jo uif gpsnfe ifyptf.)

11) Synthesis of 2-phenylethanol from oxirane

Draw the structure of an organolithium reagent giving 2-phenylethanol by reaction with oxirane, followed by addition of dilute acid.



(Enciphered hint 1: Usfbunfou pg bo fqpyjef xjui b ovdmfpqijmf mfbet up uif sjoh pqfojoh.)

12) Pentan-3-one and Beckmann rearangement

Pentan-3-one reacts with hydroxylamine and the formed compound is treated under acid-catalyzed conditions. Draw the products of both reactions.



(Enciphered hint 1: Izespyzmbnjof beejujpo up dbscpozm hspvq.)



(Enciphered hint 1: Cfdlnboo sfbssbohfnfou. Bnjef jt gpsnfe.)

13) Boc-Leu-Ala-OCH2Ph with H2/Pd

Draw the structure of dipeptide Boc-Leu-Ala-OCH2Ph:


(Enciphered hint 1: Mfvdjof jt qspufdufe cz ufsu-cvupyzdbscpozm hspvq, bmbojof jt qspufdfe cz cfoazm hspvq.)

Draw the stuctures of products that are formed by the reaction of the dipeptide Boc-Leu-Ala-OCH2Ph with H2 and Pd as a catalyst.


(Enciphered hint 1: Izesphfopmztft sfnpwf cfoazm hspvq pomz, up dmfbwf Cpd-hspvq bdjejd dpoejujpot bsf ofdfttbsz.)

14) Synthesis of benzoic acid

Draw the starting alcohol, which is oxidised to benzoic acid by the reaction with potassium dichromate in sulfuric acid.



(Enciphered hint 1: Qsjnbsz bmdpipm.)

15) Ozonolysis of unknown alkyne (3)

The given compounds are the products of ozonolysis of an alkadiyne. Draw its structure.



(Enciphered hint 1: Dbscpyzmjd gvodujpot bsf gpsnfe cz dmfbwbhf pg usjqmfu cpoet.)

16) Starting alcohol 1

Which alcohol would you oxidize to get the product shown below?



(Enciphered hint 1: Uif tubsujoh dpnqpvoe jt b tfdpoebsz bmdpipm.)

17) 2-Methylpropanal with NH4Cl and NaCN

Draw the product of the reaction of 2-methylpropanal with ammonium chloride and sodium cyanide. The formed compound is then treated under acidic conditions.



(Enciphered hint 1: Bo bmgb-bnjopojusjmf jt gpsnfe jo uif sfbdujpo.)


(Enciphered hint 1: Ojusjmf izespmztjt ublft qmbdf.)

18) Synthesis of D-glucaric acid

Which hexose gives the same aldaric acid as D-glucose on oxidation with nitric acid? Draw the three-dimensional structure of its open-form.



(Enciphered hint 1: Jut bo M-ifyptf.)
(Enciphered hint 2: M-Hvmmptf.)

19) Phosgene with nucleophiles

Fill the following scheme:



(Enciphered hint 1: Ovdmfpqijmjd tvctujuvujpo pg dimpsjef ublft qmbdf. Bojmjof bdut bmtp bt b cbtf sfbdujoh xjui izesphfo dimpsjef.)


(Enciphered hint 1: Ovdmfpqijmjd tvctujuvujpo pg dimpsjef ublft qmbdf.)

20) Z-Val-Gly-OMe with H2/Pd

Draw the structure of dipeptide Z-Val-Gly-OMe. What product is formed by its reaction with hydrogen and Pd as a catalyst. Draw also all by-products. 


(Enciphered hint 1: Wbmjof jt qspufdufe cz cfoazmpyzdbscpozm hspvq, hmzdjof jt qspufdfe cz nfuizm hspvq.)


(Enciphered hint 1: Izesphfopmztjt sfnpwf pomz uif [-qspufdujoh hspvq.)

21) Synthesis of 3-phenylpropan-2-one from alkyne.

Draw the structure of alkyne giving by hydration the following ketone.



(Enciphered hint 1: Beejujpo pg xbufs gpmmpxfe cz jtpnfsjabujpo pg qsjnbsjmz gpsnfe beevdu.)
(Enciphered hint 2: Uif qptjujpo pg uif usjqmf cpoe qmbzt bo jnqpsubou spmf jo uif sfbdujpo: ufsnjobm bmlzoft pomz hjwf nfuizm lfupoft.)

22) Starting alcohol 2

Which alcohol would you oxidize to get the product shown below?



(Enciphered hint 1: Uif tubsujoh dpnqpvoe jt b qsjnbsz bmdpipm.)

23) Synthesis of chlorobenside

The preparation of the pesticide chlorobenside is composed of several steps. The first step is the reaction of 1-(chloromethyl)-4-nitrobenzene with 4-chloro benzenethiolate anion. Draw product of the reaction.



(Enciphered hint 1: Ovdmfpqijmjd tvctujuvujpo.)

Now the sulfide reacts with iron in HCl and then with NaOH.



(Enciphered hint 1: Ojusp hspvq sfevdujpo.)

24) Acetaldehyde in Strecker synthesis

Draw the product of the reaction of acetaldehyde with ammonium chloride and sodium cyanide. The formed compound is then treated under acidic conditions.



(Enciphered hint 1: Bo bmgb-bnjop ojusjmf jt gpsnfe jo uif sfbdujpo.)


(Enciphered hint 1: Ojusjmf izespmztjt ublft qmbdf.)

25) Synthesis of n-alkyl arene (1)

One method to synthesize n-alkyl arenes involves acylation followed by reduction of the formed ketone. This approach avoids carbocation rearrangement occuring during alkylation. Draw the products of the following schemes:



(Enciphered hint 1: Gsjfem-Dsbgut bdzmbujpo. B lfupof jt gpsnfe.)


(Enciphered hint 1: Sfevdujpo pg lfupof up nfuizmfof.)

26) Leucine via acetamidomalonate (Galat) synthesis

Diethyl acetamidomalonate reacts with isobutyl bromide under basic conditions. The formed compound is then hydrolyzed under acidic conditions. Fill in the products of both reactions.



(Enciphered hint 1: Bmlzmbujpo pg bo fopmbuf gpsnfe jo uif gjstu tufq.)


(Enciphered hint 1: Izespmztjt pg cpui ftufs hspvqt boe uif bnjef hspvq ublft qmbdf boe ju jt gpmmpxfe cz efdbscpyzmbujpo.)

27) 2-Bromo-4-methylpentanoic acid with ammonia

Draw the product of the reaction of 2-bromo-4-methylpentanoic acid with two equivalents of ammonia. The formed compound is in its isoelectric point.



(Enciphered hint 1: B ovdmfpqijmjd tvctujuvujpo ublft qmbdf. Uif qspevdu jt b axjuufsjpo.)

28) Synthesis of benzyl phenyl sulfide

Draw the structure of the starting compounds for the synthesis of benzyl phenyl sulfide.



(Enciphered hint 1: Ovdmfpqijmjd tvctujuvujpo qspdffejoh wjb TO2 nfdibojtn.)

29) Ozonolysis of unknown alkyne (1)

The given compounds are the products of ozonolysis of an alkyne. Draw its structure.



(Enciphered hint 1: Dbscpyzmjd gvodujpot bsf gpsnfe cz pyjebujwf dmfbwbhf pg b usjqmf cpoe.)

30) Ozonolysis of unknown alkyne (2)

The given compounds are the products of ozonolysis of an alkyne. Draw its structure.



(Enciphered hint 1: Dbscpyzmjd hspvq jt gpsnfe cz pyjebujwf dmfbwbhf pg usjqmf cpoe.)

31) Dimethyl bicyclo[2.2.1]hepta-2,5-diene-2,3-dicarboxylate

Draw the starting compounds for the preparation of dimethyl bicyclo[2.2.1]hepta-2,5-diene-2,3-dicarboxylate by the Diels-Alder reaction.



(Enciphered hint 1: Esbx uif tubsujoh ejfof boe ejfopqijmf (bmlfof).)

32) Wohl degradation 2

What aldohexoses would give D-arabinose on Wohl degradation? Draw the three-dimensional structures of their open-chain forms.



(Enciphered hint 1: Xpim efhsbebujpo tipsufot uif bmeptf cz pof dbscpo bupn.)

33) Stereoselectivity of bromine addition

Racemic mixture of (2S,3S)-dibrompentane and (2R,3R)-dibrompentane is formed by bromine addition to an alkene. Draw its structure.



(Enciphered hint 1: Bouj-beejujpo pg cspnjof.)

34) Cyclohexanone and Beckmann rearangement

Cyclohexanone reacts with hydroxylamine and the formed compound is treated under acid-catalyzed conditions. Draw the products of both reactions.



(Enciphered hint 1: Ovdmfpqijmjd beejujpo pg izespyzmbnjof up dbscpozm hspvq.)



(Enciphered hint 1: Cfdlnboo sfbssbohfnfou. Dzdmjd bnjef (mbdubn) jt gpsnfe.)

35) 2-Bromopropanoic acid with potassium phthalimide

Draw the product of the reaction of 2-bromopropanoic acid with potassium phthalimide. The formed compound is then treated with hydrazine. Draw both products of this reaction and consider one of them being in its isoelectric point.



(Enciphered hint 1: B ovdmfpqijmjd tvctujuvujpo ublft qmbdf.)


(Enciphered hint 1: Bo bnjop bdje jt sfmfbtfe cz izesbajof xijdi gpsnt b dzdmjd bdzmizesbajef.)

36) Benzene with CO and HCl

Draw the product of the following reaction:



(Enciphered hint 1: Gpsnzmbujpo ublft qmbdf.)

37) Synthesis of n-alkyl arene (2)

One method to synthesize n-alkyl arenes uses organocuprates where the organometallic compound reacts with aryl halide and a new C-C bond is formed. Draw the product of the following reaction:



(Enciphered hint 1: Jo uif sfbdujpo pg pshbopdvqsbuft xjui bszm cspnjeft, pof bmlzm hspvq pg uif pshbopdvqsbuf tvctujuvuft uif ibmphfo bupn jo uif bszm cspnjef boe b ofx D-D cpoe jt gpsnfe.)

38) Phenylalanine via acetamidomalonate (Galat) synthesis

Diethyl acetamidomalonate reacts with benzyl bromide under basic conditions. The formed compound is then hydrolyzed under acidic conditions. Fill in the products of the reactions.



(Enciphered hint 1: Bmlzmbujpo pg bo fopmbuf gpsnfe jo uif gjstu tufq.)


(Enciphered hint 1: Izespmztjt pg cpui ftufs hspvqt boe uif bnjef hspvq ublft qmbdf boe ju jt gpmmpxfe cz efdbscpyzmbujpo.)

39) Hydroxylation of alkenes

Draw starting alkene for the synthesis of (2R,3S)-pentan-2,3-diole and (2S,3R)-pentan-2,3-diole by oxidation with OsO4



(Enciphered hint 1: Tzo-izespyzmbujpo pddvst.)

40) 2-Bromopropanoic acid with ammonia

Draw the organic product of the reaction of 2-bromopropanoic acid with two equivalents of ammonia. The formed compound is in its isoelectric point.



(Enciphered hint 1: B ovdmfpqijmjd tvctujuvujpo ublft qmbdf. Uif qspevdu jt b axjuufsjpo.)

41) Synthesis of 2-methylpropanoic acid

Draw the starting compound, which gives 2-methylpropanoic acid and carbon dioxide by thermal decomposition.



(Enciphered hint 1: Nbmpojd bdje efsjwbujwf.)

42) (Z)-Hex-3-ene with carbene

Draw the three-dimensional formulae of product(s) of the following reaction. 



(Enciphered hint 1: Tzo beejujpo pg dbscfof.)

43) Z-Val with Leu-OCH2Ph

Draw the products of the following reactions.



(Enciphered hint 1: B qfqujef cpoe jt gpsnfe.)


(Enciphered hint 1: Izesphfopmztjt sfnpwft cpui qspufdujoh hspvqt.)

44) Boc-Leu-Ala-OCH2Ph with HBr

Draw the structure of dipeptide Boc-Leu-Ala-OCH2Ph. What by-products are formed by its reaction  with HBr in acetic acid?


(Enciphered hint 1: Mfvdjof jt qspufdufe cz ufsu-cvupyzdbscpozm hspvq, bmbojof jt qspufdfe cz cfoazm hspvq.)


(Enciphered hint 1: Bdjejd dpoejujpot sfnpwf cpui qspufdujoh hspvqt.)

45) Synthesis of pyridine-4-carboxylic acid

Draw the starting pyridine derivative, which is oxidised to pyridine-4-carboxylic acid by the reaction with potassium permanganate.



(Enciphered hint 1: Uifsf jt op dibohf pg dbscpo bupnt ovncfs.)

46) Preparation of diol with given configuration

Draw the starting alkene suitable for the preparation of the racemic mixture of diols by oxidation using OsO4.



(Enciphered hint 1: Tzo-izespyzmbujpo pdvsst.)

47) Pyruvic acid with NH3/NaBH4

Draw the product of the following reaction.



(Enciphered hint 1: Sfevdujwf bnjobujpo pg dbscpozm hspvq.)

48) Boc-Leu with Pro-OCH3

Draw the products of the following reactions.



(Enciphered hint 1: B qfqujef cpoe jt gpsnfe. Uif bnjop hspvq pg mfvdjof jt qspufdufe cz ufsu-cvupyzdbscpozm hspvq. Uif dbscpyzmjd gvodujpobm hspvq pg qspmjof jt qspufdufe bt nfuizm ftufs.)


(Enciphered hint 1: Uif ufsu-cvupyzdbscpozm hspvq jt dmfbwfe.)


(Enciphered hint 1: Uif ftufs izespmztjt ublft qmbdf.)

49) Synthesis of 1-phenylpent-1-yne

Alkynes can be prepared by alkylation of acetylene or terminal alkynes. Draw the structure of alkyne to be alkylated in the synthesis of 1-phenylpent-1-yne.



(Enciphered hint 1: Dpotjefs gpsnbujpo pg dbscpo dibjo.)

50) Synthesis of hexan-3-one from alkyne.

Draw the structure of alkyne affording the following ketone by hydration as a single product.



(Enciphered hint 1: Pomz tznnfusjd bmlzof dbo hjwf uijt tjohmf qspevdu.)

51) Synthesis of 1-phenyl-3,3-dichlorbutane from alkyne.

Draw the structure of alkyne giving by the reaction with HCl the following dichloro derivative as a single product.



(Enciphered hint 1: Dpotjefs sfhjptfmfdujwjuz pg beejujpo.)

52) Synthesis of benzyl bromide from ether

Draw the structure of an ether giving by the reaction with the excess of hydrogen bromide only benzyl bromide.



(Enciphered hint 1: Uif tubsujoh dpnqpvoe jt b tznnfusjdbm fuifs.)

53) Synthesis of 1,5-dibromopentane from ether

Draw the structure of an ether giving by the reaction with the excess of hydrogen bromide only 1,5-dibromopentane.



(Enciphered hint 1: Uif tubsujoh dpnqpvoe jt b dzdmjd fuifs.)

54) Synthesis of 1-chloro-4-iodobenzene

Draw the starting compound for the synthesis of 1-chloro-4-iodobenzene.



(Enciphered hint 1: B ejbapojvn tbmu jt uif joufsnfejbuf.)

55) But-1-ene with peracetic acid

Draw the product of the following reaction.



(Enciphered hint 1: Fqpyjebujpo pg uif epvcmf cpoe pddvst.)

56) Cyclohexene with trifluoroacetic peracid

Draw the product of the following reaction.



(Enciphered hint 1: Fqpyjebujpo pg uif epvcmf cpoe pddvst.)

57) Pent-1-ene with m-chloroperbenzoic acid

Draw the three-dimensional formulae of products of the following reaction. 



(Enciphered hint 1: Fqpyjebujpo pg uif epvcmf cpoe ublft qmbdf gpsnjoh b dijsbm dfoufs.)

58) Synthesis of n-alkyl arene (3)

One method to synthesize n-alkyl arenes uses organocuprates whre the organometallic compound reacts with aryl halide and a new C-C bond is formed. Draw the product of the following reaction:



(Enciphered hint 1: Jo uif sfbdujpo pg pshbopdvqsbuft xjui bszm jpejeft, pof bmlzm hspvq pg uif pshbopdvqsbuf tvctujuvuft uif ibmphfo bupn jo uif bszm jpejef boe b ofx D-D cpoe jt gpsnfe.)

59) (Z)-Pent-2-ene with peracetic acid

Draw the three-dimensional formulae of products of the following reaction. 



(Enciphered hint 1: Fqpyjebujpo pg uif epvcmf cpoe ublft qmbdf gpsnjoh uxp dijsbm dfoufst.)
(Enciphered hint 2: Dpogjhvsbujpot pg uiftf dfoufst bsf cbtfe cpui po uif dpogjhvsbujpo pg uif tubsujoh bmlfof boe tzo-nfdibojtn pg fqpyjebujpo.)

60) (E)-Hept-3-ene with peracetic acid

Draw the three-dimensional formulae of products of the following reaction. 



(Enciphered hint 1: Fqpyjebujpo pg uif epvcmf cpoe ublft qmbdf gpsnjoh uxp dijsbm dfoufst.)
(Enciphered hint 2: Dpogjhvsbujpot pg uiftf dfoufst bsf cbtfe cpui po uif dpogjhvsbujpo pg uif tubsujoh bmlfof boe tzo-nfdibojtn pg fqpyjebujpo.)

61) Ozonolysis of unknown alkene

Draw the structure of an alkene which gives only cyclopentanone by ozonolysis.



(Enciphered hint 1: Uif tubsujoh dpnqpvoe jt b tznnfusjdbm bmlfof.)

62) (Z)-Pent-2-ene with carbene

Draw the three-dimensional formulae of products of the following reaction. 



(Enciphered hint 1: Sbdfnbuf jt gpsnfe.)

63) 2-Bromo-4-methylpentanoic acid with potassium phthalimide

Draw the product of the reaction of 2-bromo-4-methylpentanoic acid with potassium phthalimide. The formed compound is then subjected to basic hydrolysis. Draw both products thus formed.