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Flashcards in Test 3 Deck (42):
1

2

3

syn addition

4

5

trans glycol

6

Syn addition

cis glycol

7

8

syn addition

9

syn addition

10

anti-markovnikov

Br on less subs c

11

markovnikov= OH on most subs C

12

markovnikov= OH on most subs C

13

anti-addition

14

anti-addition

15

syn addition, anti-markovnikov=OH on less subs C

16

anti-addition

17

anti-addition

18

19

20

21

22

Other alkylating agents can be used: MeO and MeS

23

K2Cr2O7 in aqueous H2SO4 may also be used

24

2o alchohol most likely via SN1 so stereochem lost

25

26

best with 1o alcohols

27

Best with 1o alcohols

28

poor nucleophiles/weak bases

O with no formal charge

29

Good nucleophiles/weak bases

Cl-, Br-, I-, NC-, N3-, S-, Se- or CH3COO-, or N, S, Se with no formal charge

30

Good Nucleophile/strong base

31

1o Carbon, poor Nuc/weak base

no reaction

32

2o Carbon, poor Nuc/weak base

95% Sn1

5% E1

 

33

3o Carbon, poor Nuc/weak base

95% Sn1

5% E1

34

1o  or 2o Carbon, good Nuc/weak base

Sn2

35

3o Carbon, good Nuc/weak base

95% Sn1

5% E1

36

1o Carbon, good Nuc/strong base

E2 w/ tert-butyl-oxide (bulky base), otherwise Sn2

37

2o or 3o Carbon, good Nuc/strong base

E2

38

Sn2

One Step: Nucleophile joins alpha carbon and leaving group leaves alpha carbon, inversion of stereochem

39

Sn1

Step 1: leaving group leaves alpha carbon

Step 2: Nucleophile joins alpha carbon

racemization

40

E2

One step: Base takes Beta hydrogen, pi bond forms between alpha and beta carbons, leaving group leaves alpha carbon

-H and LG have to be antiperiplanar

41

E1

Step 1: Leaving group leaves alpha carbon

Step 2: Base takes Beta hydrogen, pi bond forms between alpha and beta carbons

both cis and trans are made

42

Good leaving groups

Cl, Br, I, N+, O+, P+, S+, sulfonate