1,3-Dipolar Cycloadditions

Question 1

Nitro e

Answer 1

Reacts as 1,3-dipole as a resonance form gives an electrophilic end and a nucleophilic end, 4π component for cycloadditions

Question 2

Making nitro es

Answer 2

Open chain: aldehydes and hydroxylamines
Cyclic: tertiary amines

Question 3

Nitrile oxides

Answer 3

Have a triple bond, generated in situ, in low cons and in presence of dienophile

Question 4

Stereoselectivity

Answer 4

Dipolarophile stereochemistry conserved

Question 5

Making nitrile oxides

Answer 5

From nitro compounds with NEt3

Question 6

Why are nitrile oxides generated in situ?

Answer 6

Not stable and dimerise rapidly

Question 7

Azide synthesis

Answer 7

Alkyl halides and sodium azide by Sn2 reaction

Question 8

Reactions with ozone

Answer 8

Two 1,3-dipolar cycloadditions and one reverse 1,3-dipolar Cycloadditions

Question 9

Ozone oxidative work up

Answer 9

H2O2 or KMnO4 gives carboxylic acids

Question 10

Ozone mild reductive work up

Answer 10

Me2S gives aldehyde/ketone

Question 11

Ozone reductive work up

Answer 11

NaBH4 gives alcohol