1 / 12

Alcohols can be thought of as organic relatives of water: H-O-H water R-O-H alcohol

Alcohols can be thought of as organic relatives of water: H-O-H water R-O-H alcohol Recall: R stands for a radical, the rest of the molecule. ••. ••. ••. ••. Classification as primary, secondary & tertiary: what kind of carbon is the OH bonded to?

traci
Télécharger la présentation

Alcohols can be thought of as organic relatives of water: H-O-H water R-O-H alcohol

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. Alcohols can be thought of as organic relatives of water: H-O-H water R-O-H alcohol Recall: R stands for a radical, the rest of the molecule. •• •• •• ••

  2. Classification as primary, secondary & tertiary: what kind of carbon is the OH bonded to? CH3CH2CH2CH2OH is a primary (or 1°) alcohol CH3CHCH2CH3 is a secondary (or 2°) alcohol OH

  3. CH3C-OH is a tertiary (or 3°) alcohol CH3 CH3

  4. Molecular Geometry & Bonding four e– pairs on O bond angle ~109° e- pairs tetrahedral O RHmolecular shape: angular or bent

  5. Nomenclature of Alcohols 1. Find longest carbon chain containing the C-OH. 2. Parent name is alkane + ol = “alkanol” . 3. Number chain so C of C-OH gets lowest possible number.

  6. Example CH3CH2CHCH2CHCH2CHCH3 OH CH3 CH2CH3 5-ethyl-7-methyl-3-octanol

  7. Example 2 HO 2 H 1 3 CHCH3 CH3 H trans-3-isopropylcyclopentanol

  8. The O-H bond of alcohols is polar covalent, just as in water. The permanent dipoles are: O C H d+ d- d+ O-H more polar than O-C other bonds to C

  9. Alcohols form “hydrogen bonds” like water does. A H-bond is an intermolecular attraction between the H of an O-H or N-H bond in one molecule and the unshared electron pairs on :O: or N: in another molecule.

  10. The molecule with the O-H or N-H in the H-bond is the H-bond donor. A moleculethat has a N: or :O: particpating in a H-bond is an electron pair donor. It is called a H-bond acceptor.

  11. ROH is both donor & acceptor for H-bonds R • • • • R • H-O O • • • H H • • • • O H O-R • • • • R = H-bond

  12. H-bonds make a molecule seem heavier -- cause an increase in boiling point compared to other compounds of same molecular weight. CH3CH2-O-CH2CH3 bp 35° C CH3CH2CH2CH2OH bp 118° C

More Related