Alcohols

Question 1

what are the characteristics of an Sn2 reaction?

Answer 1

1) strong basic nucleophile
2) weak basic leaving group
3) aprotic polar solvent
4) methyl>primary>secondary (tertiary cannot undergo
5) sterochemistry is flipped
6) rate depends on nucleophile and alkyl halide (Bimolecular)
7) leaving group must be weakly basic
8) has no intermediate, transition state is when nucleophile is attacking from backside and leaving group is leaving at the same time

Question 2

what are the characteristics of an Sn1 reaction?

Answer 2

1) neutral or weakly basic nucleophile (H2O, ROH)
2) weak basic leaving group
3) solvent is aprotic or protic polar solvent
4) must tertiary or secondary
5) racemic mixture ids formed
6) rate depends on alkyl halide (unimolecular)
7) leaving group must be weakly basic
8) intermediate is an carbon cation. this is why tertiary is most stable

Question 3

what are the characteristics of alcohols?

Answer 3

1) boiling/melting point goes up with weight, goes down with branching
2) hydrogen bonds effects boiling point
3) longer the carbon chain the less soluble
4) less acidic than water, acidity and reactivity increases from methyk»»»tertiary

Question 4

What is the reagents and the products of alcohol oxidation?

Answer 4

1) CrO3, KMnO4, K2Cr2O7- oxidizes primary alcohols to aldehydes and secondary alcohols to ketones
2) KMnO4 under abrasive conditions oxdizes primary alcohols first to aldehydes then to carboxylic acids
3) tertiary alcohols cannot be oxidized.

Question 5

What are the reagents and products of reduction of cabonyl products with a reducing agent?

Answer 5

1) NaBH, LiALH reduces aldehydes to aldehyde and secondary to ketones.
2) LiALH is a stronge reagent and will reduce esters, carboxylic acids, to primary alcohols

Question 6

What is a Grignard agent and how does it reduce alcohols?

Answer 6

A Grignard reagent is an organometallic reagent made from magnesium bromide and an alkyl or aryl group (RMgBr).

1) reduces ketones to tertiary alcohols
2) reduces formaldehydes to primary alcohols
3) reduces esters to tertiary alcohols(to of the R groups will be the same)
4) cannot reduce carboxylic acids