Tosylates, 10, 11, And 12

Front 1

Synthesis of an alkene by DEHALOGENATION of alkyl halide

Back 1

E2 using bulky bases

(DBU, t-BuOK, DBN, LDA)

polar protic solvents favor

Front 2

Synthesis of an alkene by removing TOSYLATES

Back 2

E2

eliminate the beta H, and it has to be in anti-periplanar

Front 3

1) Synthesis of an alkene by DEHYDRATION OF AN ALCOHOL

Back 3

using H2SO4 or TsOH acids

II° and III° alcohols go E1 (every time there is a carbocation intermediate there is the possibility of rearrangement)

I° and methyl alcohols go E2

CAN REARRANGE IN E1

Front 4

Strong, non-nucleophilic bases

Back 4

DBU, t-BuOK, DBN, LDA

E2

Front 5

Back 5

Tosyl chloride
TsCl

reaction goes via E1 mechanism for II° and III° alcohols, and E2 for I° and methyl alcohols. AND every time there is a carbocation intermediate (E1 mech.) there is the possibility of rearrangement.

Front 6

Back 6

Tosyl alcohol
TsOH

reaction goes via E1 mechanism for II° and III° alcohols, and E2 for I° and methyl alcohols. AND every time there is a carbocation intermediate (E1 mech.) there is the possibility of rearrangement.

Front 7

2) Synthesis of an alkene by DEHYDRATION OF AN ALCOHOL

Back 7

using POCl3 in pyridine via E2

Front 8

POCl3

Back 8

Used for the dehydration of alcohols by creating a good leaving group. Used with pyridine. E2 mechanism

Front 9

4 ways to create an alkene

Back 9

1) dehalogenation of alkyl halide
2) removing tosylates
3) dehydration of alcohol with H2SO4 or TsOH acids
4) dehydration of alcohol with POCl3 in pyridine

Front 10

Synthesis of alkyne

Back 10

From geminal and vicinal dihalides: Using at least 2 equivalents of a strong base (NaNH2,
t-BuOK, LDA). Make sure there are enough beta-hydrogens to eliminate.

Front 11

Hydrohalogenation

Back 11

Using HX (X= Cl, Br, I)
SN1 mechanism where the most stable carbocation is formed and then attacked by the halogen.

Vinyl halides (E or Z) are the product of the addition if 1 equivalent of HX is used.
Geminal dihalides is the product if 2 equivalents of HX are used. (Check mechanism)

Front 12

pyridine

Back 12

used with POCl3 in the dehydration of alcohols