Organic and Heterocyclic Chemistryh

GENERAL OBJECTIVES:

1. Know the sources, preparations, properties and uses of heterocyclic aromatic compounds

2. Know some named organic reactions involved in synthesis degradation and re-arrangement of organic compounds

3. Know some synthetic methods and reagents

4. Understand the chemistry of organometallic compounds

1.1 Define a heterocyclic compound.

1.2 List the main hetero atoms as N, O and S.

1.3 List examples of 5 membered non aromatic monoheteocyclic compounds: tetrahydrofuran, tetrahtdrothiophene and pyrolidine

1.4 List examples of 5 membered aromatic monoheteocyclic compounds - furan, pyrrole and thiophene.

1.5 Give an example of 6 membered monoheterocyclic compounds - pyridine.

1.6 Draw the structures of furan, thiophene, pyrrole and pyridine.

1.7 State Hantzch Widman rules for naming heterocyclic compounds

1.8 Name heterocyclic compounds applying the rules above.

1.9 Explain the basicity of pyridine, pyrrole and pyrolidine

1.10 Explain why aromaticity increases in the order: furan pyrrole, thiophene, benzene, pyridine.

1.11 Describe the Paal Knorr synthesis of furan, pyrrole, and thiophene.

1.12 Describe the mechanism for Paal Knorr synthesis.

1.13 Describe the physical properties of furan, pyrrole and thiophene.

1.14 Describe the Hantzsch synthesis of pyridine

1.15 Describe the mechanism of the Hantzsch synthesis

1.16 Describe the following for 5 and 6 membered monoheterocyles:

(a) Electrophilic substitution at carbon atoms - Nitration, sulphonation, halogenation, acylation, diazocoupling, nitrosation and mercuration.

(b) mechanism of the above reactions and explanation of the regioselectivity

(c) Reactions with acids - ring opening, polymerization, picrate - formation and oxidation.

1.17 List examples of 5 membered polyheterocyclics like imidazole thiazole, pyrazole, oxazole and examples of 6 membered poly heterocyclics as pyrazine, pyrimidine
and pyridazine.

1.18 List polycyclic derivatives of 5 membered ring systems like indole, benzo-furan, benzathiphene carbazole and 6 membered polycyclic derivatives like acridine.

1.19 Describe the occurrence of indole, and the indole alkaloids

1.20 Describe the methods of synthesis of indoles:

(a) the Fisher indole synthesis

(ii) the Bishchier indole synthesis

(iii) the Madelling indole synthesis

1.21 Explain the chemical properties of indole - oxidation, addition reaction, substitution reaction, reduction reaction, Erlich test.

1.22 State the sources of quinoline.

1.23 Describe the Skramp’s synthesis of quinoline from amylamines and â-unsaturated carbonyl compounds.

1.24 Explain the chemical properties of quinoline - notration, sulphonation, halogenation, oxidation, reduction.

1.25 Describe the relationship between quinoline and quinine, and the use of quinine to treat malaria

2.1 Describe Gabriels’ synthesis off primary amines.

2.2 Describe Arndt-Eistert, and Baeyer - Villiger reaction for the synthesis of carboxylic acids.

2.3 List examples of peracids as oxidizing agents in the Baeyer Villiger reaction such as perbenzoic acid, peracetic acid.

2.4 Explain why Baeyer-Villiger reaction is applicable to aliphatic and aryl ketones without double bonds.

2.5 Describe Aldol, Claisen, Beckmann and Perkin condensation reactions.

2.6 Explain the Sandmeyer and Gattermann’s reaction of the displacement of diazomium groups.

2.7 Describe Friedel-crafts alkylation and acylation; Haller-Bauer alkylation.

2.8 Describe Wittig reaction. 

2.9 Describe Diels-Alder reaction

2.10 Describe Walden inversion in the reaction of bases with alkylhalides.

2.11 Describe Reformatsky reaction (see Organometallic compounds).

2.12 Describe Wohl-Ziegler bromination of alkenes.

2.13 Describe Michael’s addition reaction.

2.14 Describe Williamson’s synthesis of ethers.

2.15 Describe Kiliani-Fisher synthesis of cyanohyin like Rosemund Wolff-Kischner and Clemmenson’s reactions.

2.16 Describe the following degradation rearrangements reactions:

(a) Ruff’s degradation

(b) Curtis degradation

(c) Schmidth degradation

(d) Wagner-Meerwein degradation

(e) Beckmann degradation

(f) Wohl’s degradation

(g) Hoffman’s degradation

3.1 Describe methods of formation of c-c bonds by the use of Organometallic reagents, base catalysed and acid catalysed condensation reactions.

3.2 List reagents for organic synthesis such as Grignard reagents (RMgBr), strong bases (e.g. NaOH, NaNH2 etc), acetoacetic ester, diethyl malonate, phosphonium and sulphorium ylids, peracids.

3.3 Describe the use of enamines and protecting groups for organic synthesis.

4.1 Define an organometallic compound.

4.2 List examples of organometallic compounds.

4.3 List and describe physical and chemical properties of organometallic compounds.

4.4 Describe the preparation of organometallic compounds (Grignard reagent RMgBr).

4.5 Apply Grgnard reagent to organic synthesis.

4.6 Describe the reactions of Grignard reagents with organic halides (both alkyl and benzyl halides, alcohols, ketones, acid chlorides, esters, epoxides, and amides).

4.7 Describe the preparation of organosodium, organolithium and organocadmium compounds.

4.8 List properties of the compounds in 4.7 above.

4.9 Compare the reactivities of compounds in 4.7 above with Grignard reagents.

4.10 Describe the preparation of zinc-alkyls.

4.11 List the properties of zinc-alkyls.

4.12 Discuss the use of zinc-alkyls in synthesis by using appropriate examples