Hydroxy Functional Group - Alcohols | Organic Chemistry 1

Because of the electronegativity of the oxygen, alcohols exhibit molecular polarity
⇒ Alcohols are soluble in water and polar solvents

The hydroxy hydrogen enters into hydrogen bonding with other alcohol molecules
⇒ High boiling point compared to the corresponding alkanes

Alcohols are amphoteric
⇒ they can be deprotonated by strong bases or protonated by strong acids

- Find the longest chain containing the OH.

- Number the chain starting at the end nearer the OH. 
(If equal, begin at the end nearer the first branch point).

- Place the number of the position of OH before the parent name.
Use the suffixes diol, triol ... if more than one OH.
The names of the substituents are added as prefixes.

- For cyclic alcohols, the carbon bearing the OH receives the number 1
(it does not need to be mentioned if there is only one substituent).

To prevent the competition between SN and E reactions ⇒ replace the halogen atom by a good leaving group:

Alcohols can be synthesized by reduction of carbonyls using H^- donors (NaBH₄ or LiAlH₄).
H^- reacts with an electrophile and so with the C of the carbonyl.

Oxydation and Reduction of alcohols:
 

Alcohols can be synthesized by using organometallics, R^- donors.

3 types of organometallics (R = alkyl chain):
- Alkyl lithium: RLi (R^-Li⁺)
- Grignard reagent: RMgBr (R^-BrMg⁺)
- Gilman reagent: R₂CuLi (R^-RCu⁺Li)
 

Synthesis of Organometallics:

R^- (like H^-) reacts with an electrophile and so with the C of the carbonyl:

Reactions of Organometallics R-M (M= Li, MgBr or RCuLi):

- synthesis of alcohol + C-C bond formation

- C-C coupling reactions (only with Gilman reagent)

- strong reaction with water