! 1! Some!Practice!Problems!for!the!Carbonyls!Test!3!

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Some Practice Problems for the Carbonyls Test 3

RETROSYNTHESIS PRACTICE: Design synthesis for the following, FROM ALCOHOLS

WITH NO MORE THAN 5 CARBONS. YOU MAY ALSO USE ESTERS, or any inorganic

agents (PPh3, PBr3, PCC, H2CrO4, etc.)

No other alkene

structural isomers allowed

(in other words, don't make

1.

an alcohol elimination reaction)

Tex

O OH

2.

Alkene with no carbonyl: Wittig Remember to make each piece from starting alcohol. Often two solution. 1. PBr3 2. PPh3 3. BuLi good way to convert alcohol to Wittig reagent

Beta-hydroxy carbonyl ==> Aldol reaction. Carbonyl that provides and enolate, and an aldehyde as an electrophile (beta)

OO

3.

1,3 dicarbonyl (beta-keto carbonyl) ==> Claisen reaction

Ester electrophile

O

Tex

4.

OH O

5.

alpha-beta unsaturated carbonyl = enone ==> Aldol condensation Aldehyde as electrophile

Beta-hydroxy carbonyl ==> Aldol reaction. Carbonyl that provides and enolate, and an aldehyde as an electrophile (beta)

2

O

6.

7.

Tex

OO

8.

OO O

9.

Tex

3

SYNTHESIS DESIGN PRACTICE: Provide Reagents for the Following Transformations. You

may use anything you like, so long as you involve the starting chemical specified.

1.

OH

Ph

O

Ph

2.

Tex

OH

OH O

OO

3.

OH

4.

OO

5.

Tex

O

6.

O

O OCH3

O

7.

No other alkene isomers form

O OH Ph

O

OH

Ph O

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