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Flashcards in Substitution and Elimination Facts Deck (47)
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1

What happens during a substitution reaction?

The leaving group leaves and it is replaced by a nucleophile

2

What is the substrate?

The thing connected to the leaving group

3

What are the best substrates?

Ch3 > 1 > 2 > 3

4

What is the leaving group?

The thing that leaves off of the substrate

5

What makes a good leaving group?

NEUTRAL atoms

- leaving groups can leave by receiving the electrons from breaking the bond..... if they already have a lot of electrons and are (-), then they won't want to break off

6

What is the periodic trend for leaving groups?

Increases DOWN and to the RIGHT

7

What is the nucleophile?

It is the thing that replaces the leaving group on the substrate

8

What makes a good nucleophile?

ANIONIC atoms

* Nucleophiles are like bases, and strong bases have (-) charges

9

What is the solvent?

The thing being mixed with the reactants

10

What are the two different types of solvents?

Aprotic and protic solvents

11

Define aprotic solvents

Solvents that can NOT H-bond

12

Define protic solvents

Solvents that CAN H-bond

13

What happens in a SN2 reaction?

- 1 step : The leaving group leaves and the nucleophile attacks from behind

14

What to watch out for in SN2 reactions?

Stereochemistry

15

Define stereochemistry

cis and trans

16

When there is stereochemistry in a SN2 reactant, what happens to the product?

Inversion of stereochemistry

17

Define inversion of stereochemistry

cis -> trans

trans ->cis

18

SN2 Substrate

Ch3 > 1 > 2 > 3

19

SN2 leaving group

Good leaving group

20

SN2 nucleophile

Good nucleophile

ANIONIC

21

SN2 solvent

aprotic

22

What happens in an SN1 reaction?

- 2 steps : the leaving group leaves then the nucleophile attacks

23

What to watch out for in SN1 reactions

Carbocation rearrangement and stereochemistry

24

What stabilizes carbocations?

ressonance

25

What are the two ways to rearrange a carbocation?

- Alkyl shifts

- Hydride shifts

26

SN1 substrate

3 > 2 > 1 > Ch3

27

SN1 leaving group

Good leaving group

28

SN1 nucleophile

Weak nucleophile

NEUTRAL

29

SN1 solvents

protic

30

What happens during an elimination reaction?

A base (nucleophile) takes an H and the electrons from that broken bond form a double bond