Textbook Notes (369,198)
Canada (162,457)
Chemistry (303)
CHM247H1 (26)
Barb Morra (11)
Chapter 17

Ch.17 Summary.docx

13 Pages
117 Views

Department
Chemistry
Course Code
CHM247H1
Professor
Barb Morra

This preview shows pages 1,2,3. Sign up to view the full 13 pages of the document.
Description
CHM 247 CH.17 Alcohols and Phenol • Alcohol: A compound with an –OH group bonded to a saturated, sp -hybridized carbon, ROH. • Phenol: A compound with an –OH group directly bonded to an aromatic ring, ArOH. • Enol is a hydroxyl group bonded to a carbon in a double bond. • 17.1 NamingAlcohols and Phenols • Can be primary, secondary, or tertiary. • Rules: 1) Longest chain with the hydroxyl group. Replace the –e with –ol. 2) Number the chain. 3) List in alphabetical order. • Phenol is used as the parent name rather than benzene. 17.2 Properties of Alcohols and Phenols • Alcohols and phenols have a higher than expected BP due to H-bonding. • Alcohols and phenols are both weakly basic and weakly acidic. • Weak base: • Alkoxide ion: The anion RO formed by deprotonation of an alcohol. • Phenoxide ion: The anion of a phenol, ArO .- • Weak acid: • Simple alcohols are about as acidic as water. Phenols are substantially more acidic than water. • The bulkier the alcohol the weaker the acid. • Induction by EWGs polarize the O-H bond and increase acidity. • Alcohols don’t react with weak bases such as amines or bicarbonate ion. • Alcohols do react with alkali metals, strong bases (NaOH, NaH, NaNH ),2and Grignard reagents (RMgX). • • Phenols are soluble in NaOH due to being more acidic. • Substituted phenols can be more or less acidic than phenol depending on the substituent being an EWG or an EDG. Phenols with an EWG are more acidic. Phenols with an EDG are less acidic. 17.3 Preparation of Alcohols: A Review • • Hydroboration: Syn, non-Markovnikov. Oxymercuration-demercuration: Markovnikov. • • OsO y4elds cis product. Epoxide opening yields trans. 17.4 Alcohols from Carbonyl Compounds: Reduction • Most common method of preparation is the reduction of a carbonyl compound. Reduction of Aldehydes and Ketones • Aldehydes are easily reduced to primary alcohols and ketones are reduced to secondary alcohols. • • Only strong enough to reduce aldehydes and ketones. Solvents are alcohols. • Stronger than NaBH .4Reduces other carbonyls like esters and carboxylic acids, though 2 equivalents of hydride are needed. Reacts violently with H 2, dry solvents are used (ether, THF). Reduction of CarboxylicAcids and Esters • Not as fast as aldehydes or ketones being reduced. 17.5 Alcohols from Carbonyl Compounds: Grignard Reaction • • When a proton is present, Grignard reagents will not work. • • • Carboxylic acids do not give addition products with Grignard reagents because the acidic carboxyl hydrogen reacts with the basic Grignard reagent to yields a HC and a magnesium salt. • Grignard reagents can’t be prepared from an organohalide if other reactive functional groups are present on the same molecule. • 17.6 Reactions of Alcohols Conversion ofAlcohols intoAlkyl Halides • Tertiary alcohols react with HCl or HBr by a S N mechanism. No necessary change in stereocenter. Primary and secondary alcohols are more resistant to acid and are best converted with treatment of SOCl o2 PBr th3ough an S 2 mNchanism. • •
More Less
Unlock Document

Only pages 1,2,3 are available for preview. Some parts have been intentionally blurred.

Unlock Document
You're Reading a Preview

Unlock to view full version

Unlock Document

Log In


OR

Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


OR

By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.


Submit