1 / 50

HL organic chemistry topic 20

HL organic chemistry topic 20. More functional groups Amines NH 2 Draw 1-aminopropane (propanamine) and give condensed formula. Methylamine (old) aminomethane IUPAC 1,6-diaminohexane. 1-butylamine, 1-butanamine, 1-aminobutane (all the same). Secondary amines.

devaki
Download Presentation

HL organic chemistry topic 20

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. HL organic chemistry topic 20 • More functional groups • Amines • NH2 • Draw 1-aminopropane (propanamine) and give condensed formula

  2. Methylamine (old) aminomethane IUPAC • 1,6-diaminohexane

  3. 1-butylamine, 1-butanamine, 1-aminobutane (all the same)

  4. Secondary amines • N-methylpropanamine (name the longest chain)

  5. Tertiary amines • CH3CH2N(CH3)2 name and draw • N,N-dimethylpropanamine

  6. Esters • Yeah, already done

  7. Amides • R-CO-NH2 • Name the longest carbon chain followed by amide (amides on the end) • propanamide

  8. 2-methylpropanamide

  9. Secondary amides • N-methylproanamide

  10. N,N-dimethylpropanamide

  11. Nitriles • R-CN • Used to be cyanides C2H5CN ethyl cyanide • Now propanenitrile • Draw it

  12. Draw ethanenitrile • Pentanenitrile? • Do question 1

  13. Nucleophilic substitution reactions • -ions or molecules with a nonbonding pair of electrons • Act as Lewis bases • Use curly arrows to show movement • H2O, OH-, CN-, NH3

  14. SN2 mechanism • Ammonia and bromoethane forms ethylamine and hydrogen bromide • Need conc. NH3 and sealed tube for pressure

  15. forms N-ethylethanamine then N,N-diethylethanamine • Eventually tetraethylammonium bromide

  16. Make propan-2-amine

  17. Needed for halogenoalkane reactions • Show bromoethane with potassium cyanide(in ethanol and reflux) to form propanenitrile • Show the SN2 mechanism

  18. Now reduce it to propanamine

  19. Factors affecting the rate of nucleophilic reactions • electronegative can easily donate e- pair • CN->OH- >NH3 > H2O • Strength of carbon to halogen bond remember I >Br to F

  20. Type of mechanism SN1(tertiary) > secondary (mixture) > SN2 (primary) • Do question 2-5 • Lab activity • Do questions 17-19 page 399 for HW

  21. Elimination reactions • Halogenoalkanes with hot NaOH in alcohol to alkene • With water and Br- also formed • C2H5Br to C2H4 • OH- in hot alcohol, reflux

  22. E2 (elimination bimolecular)mechanism to form alkene • See pages 400 and 401 • Do questions 20-21 page 401 for HW

  23. Condensation reactions • Acids and alcohols with H2SO4 as catalyst • H2O byproduct (makes a longer chain) • Pineapple is ethyl butanoate

  24. Esters have no H bonding, are more volatile, less soluble in water • Naturally occurring fats and oils

  25. Acids with primary amines form secondary amides • Ethanoic acid and metanamine

  26. Secondary amines and acids form a peptide bond (tertiary amide) • Amino acids form peptide bonds

  27. Alanine and glycine can form 2 dipeptides • Many amino acids form proteins

  28. Do question 6-7 • Animation

  29. Condensation polymerization • To make polypeptides or proteins • Hexane-1,6-dioic acid with 1,6-diaminohexane to form polyamide nylon

  30. Polyesters like dacron • Benzene-1,4-dicarboxylic acid and ethane-1,2-diol draw this monomer (polyester) • PET is polyethene-1,4-benzoate used for plastic bottles • Do question 8 • Do questions 22-24 page 406 for HW

  31. Reaction pathways • Add nitrile, amine and amide to your algorithms

  32. How can bromoethane be converted to propanamine?

  33. Convert ethanol to N-methylethanamide using another organic compound • Do questions 25-27 page 407 for HW • Lab activity

  34. Stereoisomerism • Same molecular and structural formula but atoms arranged differently in space

  35. geometrical • Multiple bonds cannot be rotated • Cis trans • But-2-ene • Build this

  36. Draw and name the geometric isomers of but-2- enedioic acid

  37. Similar properties but not the same • Depends on the functional group • Polarity, shape and symmetry of the molecules

  38. Cis and trans 1,2-dichlorethene • Which has the higher boiling point, melting point

  39. Can occur in cyclic compounds • 1,2-dimethylcyclopropane cis and trans

  40. 5 isomers of dichlorocyclobutane • 2 are cis 2 are trans

  41. Cis and trans-but-2-ene-1,4-dioic acid • trans strong H bonding mp 286 oC and cannot form cyclic anhydride

  42. H bonding in molecule • cis mp 131 oC with heat trans can form cis-but-2-ene-1,4-dioic anhydride • lab activity

  43. Optical isomerism • Asymmetric carbon atom (chiral) 4 different groups • Make a model of a chiral carbon and its stereoisomer • Mirror images = enantiomers • Do question 9

  44. Drawings of enantiomers • Use an asterisk to designate the chiral carbon • Butan-2-ol

  45. 2-bromobutane

  46. Draw the enantiomers of 2-hydroxypropanoic acid (lactic acid) Mark the chiral carbon atom and show the plane of the mirror

  47. Demonstration of plane polarized light • Dextrorotatory d- rotated clockwise with a polarizor to get maximum intensity • Lavorotatory l- counter clockwise • Mixture of both is racemic • animations

  48. Usually same chemical and physical properties • Exception is when they interact with other optically active substances • 2-amino acids must be l (-) form • Sugars d (+) form

  49. Thalidomide in 1960’s • For morning sickness • One enantiomer causes malformations in the fetus

  50. Do question 10-11 • Do questions 28-30 page 415 for HW • Do questions 12-17 on page 74 of your study guide • Do questions 13-20 pages 416-418 in your textbook

More Related