Organic Chemistry 1 for Majors Test 4

SN2 Elementary Step

The Nuclephilic group bonds to carbon as the Leaving group attached leaves

SN1 Elementary Step

The Leaving group leaves on its own and the Nucleophilic group attaches to the carbon to replace it

What is the thing that SN2 and SN1 can have in common?

The product can be the same

Intermediate

The thing that occurs in a local minimum of energy along the reaction

Can intermediate steps be isolated?

No, it is fleetign and can only be observed

Mechanisms that contain "n" amount of steps contain…

"n" amount of transition states

E2 Elementary Step

The base bonds with a proton and then a pi bond is formed with the leftover electrons as the leaving group leaves, (this all happens simultaneously)

E1 Elemetary Step

The Leaving group leaves on its own, then the base takes the proton and the electrons left behind make a pi bond

What do the X1 elementary steps have in common?

The Leaving groups leaving is the first action

What do the X2 elementary steps have in common?

The Nucleophile or base bonds

SN2 Rate =

kSN2 [Nu]

SN1 Rate =

kSN1 [R]

E2 Rate =

kE2 [:B]

E1 Rate =

kE1 [R]

What happens to the chemical undergoing SN2?

It undergoes stereochemical inversion.

Stereochemical Inversion

If the leaving group is on a wedge, the nucleophile will bond on dashes and vice versa

What is the Stereochemical Inversion known as?

"The Backside Attack" KACHOW

What is the stereochemistry of the SN1 reaction?

Racemic mix of diastereomers (50:50 mix of R and S)

Stereochemistry of E2

Usually (but not always) an E alkene (complex)

What orientation do the bonds that break in E2 need to be?

Anticoplanar (opposite to each other but still in the same plane)

Stereochemistry of E1

An alkene where the least amount of steric strain is the main product