ORGANIC CHEMISTRY 1

1. ORGANIC CHEMISTRY 1 Lecture 1 Different manners of writing and drawing structural formulas of organic molecules Systematic (IUPAC) and common names of hydrocarbons Systematic (IUPAC) and common names of compounds with single functional group.

2. Language of organic chemists

3. Types of organic compounds HYDROCARBONFRAMEWORK HYDROCARBONFRAMEWORK FUNCTIONAL GROUP

4. Drawing and naming of organic structures

5. Rules for drawing skeletal structures • Carbon atoms are not shown. They assumed to be at each intersection of two lines (bonds) and at the end of each line. Occasionally, a carbon atom might be indicated for emphasis or clarity. • Hydrogen atoms bonded to carbon are not shown. Since carbon has always valence of 4, we mentally supply the correct number of hydrogen atoms to fill the valence of each carbon. • All atoms other than carbon and hydrogen (heteroatoms)are indicated.

6. ALKANES (saturated hydrocarbons, aliphatic hydrocarbons) • Do not contain functional groups

7. Functional groups. • With carbon-carbon multiple bonds Alkene Alkyne Arene (aromatic ring)

8. Types of functional groups. • With carbon singly bonded to an electronegative atom Alkyl halide Alcohol Ether Amine Thiol (thioalcohol) Sulfide (thioether)

9. Functional groups. • With carbon-oxygen double bond (carbonyl groups) Aldehyde Ketone Carboxylic acid Ester Amide Acid chloride

10. Naming alkanes according to IUPAC rules Prefix—Parent—Suffix What are substituents?How many carbons?What family?

11. Parent names of chain alkanes from C1to C20 C1 methane C2 ethane C3 propane C4 butane C5 pentane C6 hexane C7 heptane C8 octane C9 nonane C10 decane C11 undecane C12 dodecane C13 tridecane C14 tetradecane C15 pentadecane C16 hexadecane C17 heptadecane C18 octadecane C19 nonadecane C20 eicosane

12. Naming alkanes according to IUPAC rules Step 1. Find the parent hydrocarbon – that means find the longest continuous carbon chain in the molecule: If 2 different chains are equal, choose the one with the larger number of branch points:

13. Naming alkanes according to IUPAC rules Step 2. Number the atoms in the main chain beginning at the end nearer the first branch point: If there is branching an equal distance away from both ends, begin numbering at the end nearer the second branch point:

14. Naming alkanes according to IUPAC rules Step 3. Identify and number the substituents: on C3, CH2CH3 (3-ethyl) on C2, CH3 (2-methyl) on C4, CH3 (4-methyl) on C4, CH3 (4-methyl) on C7, CH3 (7-methyl) on C4, CH2CH3 (4-ethyl) 3-ethyl-4,7-dimethylnonane4-ethyl-2,4-dimethylhexane Step 4. Write the name as a single word using hyphen to separate different prefixes, and commas to separate numbers. Prefixes should appear in alphabetical order.

15. Naming alkanes according to IUPAC rules Step 5. When a substituent of the main chain has its own sub-branching. The name of complex substituent is formed applying the steps 1-4 just as if the substituent was a compound itself. Numbering in complex substituent starts alwaysat the point of attachment to the main chain.

16. Common names of straight-chain and branched-chain alkyl substituents derived from C3 – C4 alkanes propane propyl isopropyl butane butyl sec-butyl

17. Common names of straight-chain and branched-chain alkyl substituents derived from C4 – C5 alkanes isobutane isobutyl tert-butyl pentane pentyl

18. Common names of straight-chain and branched-chain alkyl substituents derived from C5 alkanes isopentane isopentyl tert-pentyl neopentane neopentyl

19. Naming cycloalkanes according to IUPAC rules Step 1. Use the cycloalkane name as the parent name When alkyl substituent contains more carbons than ring, use alkane as parent name.

20. Naming cycloalkanes according to IUPAC rules Step 2. In substituted cycloalkanes number the atoms in the ring starting at the point of attachment so as to arrive at the lowest sum. When different substituents are present, they are numbered by alphabetical priority. correct wrong

21. Nomenclature of alkenes according to IUPAC rules Alkenes are named according to a series of rules similar to those developed for alkanes, with the suffix –ene used instead of -ane to identify the family. Step 1. Find the parent hydrocarbon – that means find the longest carbon chain containing the double bond:

22. Step 2. Number the atoms in the chain beginning at the end nearer the double bond. If the double bond is equidistant from the two ends, begin at the end nearer the first branch point. This rule assures that the double bond carbons receive the lowest possible numbers: 2-hexene 2-methyl-3-hexene Step 3. Write the full name numbering the substituents according to their position in the chain and listing them alphabetically. Indicate the position of the double bond by giving the number of the first alkene carbon. If more than one double bond is present indicate the position of each and use the suffixes -diene, -triene, -tetraene, and so on. 2-ethyl-1-pentene 2-methyl-1,3-butadiene

23. Common names of unsaturated substituents accepted by IUPAC methylene ethylidene vinyl allyl ethenyl 2-propenyl

24. Common and systematic names of some alkenes Systematic name Common name Ethene Ethylene Propene Propylene 2-Methylpropene Isobutylene 2-methyl-1,3-butadiene Isoprene

25. Naming cycloalkenes according to IUPAC rules Cycloalkenes are named in a similar way, but because there is no chain end to begin from, we number the cycloalkene so that the double bond is between C1 and C2 and the first substituent has as low number as possible. 1-methylcyclohexene1,4-cyclohexadiene1,5-dimethylcyclopentene

26. Nomenclature of alkynes according to IUPAC rules Alkynes follow the general rules of hydrocarbon nomenclature. The suffix –yne is used to denote an alkyne, and the position of the triple bond is indicated by its number in the chain. Numbering always begins at the chain end nearer the triple bond so that the triple bond receives as low a number as possible. 6-methyl-3-octyne

27. Compounds with more than one triple bond are called diynes, triynes and so forth; compounds containing both double and triple bonds are called enynes (not ynenes). Numbering of an enyne chain always starts from the end nearer the first multiple bond, whether double or triple. When there is a choice in numbering, though, double bonds receive lower numbers than do triple bonds. 4-methyl-7-nonen-1-yne 1-hepten-6-yne 4-methylnon-7-en-1-yne hept-1-en-6-yne Names of alkynyl substituents: ethynyl 1-propynyl 1-butynyl

28. Nomenclature of arenes BenzeneEthylbenzeneBromobenzene Disubstituted benzene derivatives: ortho-dibromobenzene meta-dibromobenzene para-dibromobenzene o-dibromobenzene m-dibromobenzene p-dibromobenzene 1,2-dibromobenzene 1,3-dibromobenzene1,4-dibromobenzene

29. In tri- and more substituted benzenes the lowest possible numbers are used, and substituents are listed alphabetically 1,2-dibromo-4-methylbenzene1,3,5-trimethylbenzene1,4-dibromo-2,5-dimethylbenzene

30. Aryl substituents Phenyl Benzyl C6H5-C6H5CH2- Ph- PhCH2- Bn

31. Common names of some alkylbenzenes p-Cymene o-Xylene m-Xylene p-Xylene 1-isopropyl-4-methylbenzene 1,2-dimethylbenzene 1,3-dimethylbenzene 1,4-dimethylbenzene Cumene Mesitylene Styrene Isopropylbenzene 1,3,5-trimethylbenzene Vinylbenzene Ethenylbenzene

32. Some aromatic hydrocarbons found in coal tar Benzene Toluene ortho-Xylene Indene Naphthalene Biphenyl Anthracene Fluorene Phenanthrene

33. Every organic compound consists of hydrocarbon framework (and some contain also functional group) Type of skeleton andfunctional group determine both - physical propertiesand chemical reactivity of compound.

34. Aliphatic aldehyde Aromatic aldehyde Reactivity of functional group essentially the same, reactivity of hydrocarbon part different

35. Aliphatic amine Aliphatic carboxylicacid Reactivity of hydrocarbon part essentially the same, reactivity of functional group totally different

36. Overview of functional groups in organic molecules

37. Families of organic compounds Family name Functional group structure Example Name ending -ane pentane Alkane -ene 2-pentene Alkene -yne 1-pentyne Alkyne None benzene Arene

38. None 3-chloropentane Halide -ol 2-pentanol Alcohol ether dipentyl ether Ether

39. -amine pentylamine Amine -nitrile pentanenitrile Nitrile None 3-nitropentane Nitro

40. -thiol 2-pentanthiol Thiol sulfide dipentyl sulfide Sulfide sulfoxide dipentyl sulfoxide Sulfoxide sulfone dipentyl sulfone Sulfone

41. -al pentanal Aldehyde -one 2-pentanone Ketone

42. -oic acid pentanoic acid Carboxylic acid -oate ethyl pentanoate Ester

43. Amide -amide pentanamide -amide N-methylpentanamide -amide N,N-dimethylpentanamide

44. -oyl chloride pentanoyl chloride Carboxylic acid chloride Carboxylic acid anhydride -oic anhydride pentanoic anhydride

45. Naming of compounds containing single functional group

46. In chain structures with functional group • containing carbon, like: • nitrile (-CN), • aldehyde (-CHO), • carboxylic acid (-COOH), • ester (-COOR), • amide (-CONH2), • acid chloride (-COCl) carbon atom of functional group has to be number 1

47. When functional group containing carbon, like: • nitrile (-CN), suffix -nitrile • aldehyde (-CHO), suffix -al • carboxylic (-COOH), suffix -oic acid • ester (-COOR), suffix -oate • amide (-CONH2), suffix -amide • acid chloride (-COCl) suffix -oyl chloride • is directly linked to the ring, the suffix in the IUPAC name is changed to: • -carbonitrile, • -carbaldehyde, • -carboxylic acid, • -carboxylate, • -carbonamide, • -carbonyl chloride

48. and ring carbon bonded to functional group is assign as number 1 !!!

49. EXAMPLES 1 1 Propanenitrile Cyclopropanecarbonitrile 1 1 Butanal Cyclobutanecarbaldehyde 1 1 Pentanoic acid Cyclopentanecarboxylic acid

50. EXAMPLES 1 1 Ethyl hexanoate Ethyl cyclohexanecarboxylate 1 1 Heptanamide Cycloheptanecarbonamide 1 1 Octanoyl chloride Cyclooctanecarbonyl chloride