1 / 19

Alkene/Alkyne Addition Reactions

Alkene/Alkyne Addition Reactions. The double and triple bonds present in alkenes and alkynes, respectively, make them much more reactive than alkanes. Alkenes and alkynes undergo addition reactions

zoltin
Télécharger la présentation

Alkene/Alkyne Addition Reactions

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. Alkene/Alkyne Addition Reactions • The double and triple bonds present in alkenes and alkynes, respectively, make them much more reactive than alkanes. • Alkenes and alkynes undergoaddition reactions • a reaction in which parts of a reactant are added to the two atoms that make up a double or triple bond

  2. Alkene/Alkyne Addition Reactions • Two simple addition reactions: H H H H C = C + Br2 H - C - C - H H H Br Br Cl Cl H - C C - H + 2 Cl2 H - C - C - H Cl Cl

  3. Alkene/Alkyne Addition Reactions • Some of the common reactants that can add to alkenes and alkynes include: • Br2 • I2 • Cl2 • H2 (requires a transition metal catalyst) • H2O (requires a strong acid catalyst) • HBr • HCl • HI

  4. Alkene/Alkyne Addition Reactions Example: Write the structure of the product that forms when 1-butene reacts with the following reagents (individually): Br2 H2 + Ni catalyst HBr

  5. Alkene/Alkyne Addition Reactions • Markovnikov’s Rule:The major product obtained from the addition of an unsymmetrical reagent such as H-Br, H-Cl, or H-OH to an alkene or alkyne is the one obtained when the H atom of the reagent is added to the C atom of the multiple bond that already has the greater number of H atoms. “The rich get richer”

  6. Alkene/Alkyne Addition Reactions Example: Write the structure of the product that forms when 1-propyne reacts with the following reagents (individually): Br2 (excess) H2 (excess) with Ni catalyst HBr (excess)

  7. Hydroxyl groups Alcohols • Alcohols: • hydrocarbon derivatives in which one or more of the H atoms has been replaced by a hydroxyl group (alcohol functional group) C - O - H OR C - OH

  8. Alcohols • Alcohols are named in the exact same manner as alkanes, alkenes, and alkynes except: • To find the base name, drop the “e” from the name of the corresponding alkane and add “ol” • Use the carbon number to identify the position of the alcohol. CH3CH2CHCH3 OH CH3CH2CH2OH 1-propanol 2-butanol

  9. Alcohols Examples: Draw the structures for the following alcohols. Methanol Ethanol 2-Propanol 2-methyl-2-propanol

  10. Alcohols • The position of the alcohol in the chain has a significant impact on the reactivity of the alcohol. • A primary alcohol (1o) is an alcohol in which the OH group is attached to a carbon which is bonded to only 1 other C atom. • CH3CH2OH

  11. Alcohols • A secondary alcohol (2o) is an alcohol in which the OH group is attached to a carbon which is bonded to two other carbon atoms. • CH3CHCH3 OH • CH3CH2CHCH2CH3 OH

  12. Alcohols • A tertiary alcohol (3o) is an alcohol in which the OH group is attached to a C which is bonded to three other carbon atoms. CH3 CH2CH3 CH3CCH3 CH3CH2CCH3 OH OH

  13. Alcohols Example: Identify the following alcohols as 1o, 2o, or 3o. Name each alcohol. CH3 CH3 CH3CHCH2OHCH3CH2CCH3 OH CH3CHCH2OH OH

  14. Carboxyl group Reactions of Carboxylic Acids • Carboxylic acids contain a carboxyl group: O CH3C-O-H OR CH3CO2H

  15. Reactions of Carboxylic Acids • Carboxylic acids can participate in a variety of reactions: • acid-base reactions • similar to those of inorganic (without C-C bonds) acids • condensation reactions • esterification • amidation

  16. Reactions of Carboxylic Acids • Esterification: • a condensation reaction in which a carboxylic acid reacts with an alcohol to form an ester and water. O O CH3C - OH + HO-CH2CH3 CH3C-O-CH2CH3+ H2O

  17. Reactions of Carboxylic Acids Example:Predict the products formed during the following reactions. O CH3C - OH + CH3 CH2CH2OH O C - OH + CH3OH

  18. Reactions of Carboxylic Acids • Amidation: • a condensation reaction in which a carboxylic acid reacts with an amine that contains a hydrogen bonded to nitrogen to form an amide and water O O CH3C - OH + H2N-CH2CH3 CH3C-NH-CH2CH3+ H2O

  19. Reactions of Carboxylic Acids Example:Predict the products formed during the following reactions. O CH3 CH2C - OH + CH3CH2NH2 O C - OH + CH3NH2

More Related