Reactions of Alcohols

Question 1

Dehydration to form Alkenes (using strong acid)(H2SO4 or TsOH)

Answer 1

1. Order of Reactivity: R3COH>R2CHOH>RCH2OH
2. The mechanism for secondary and tertiary ROH is E1; carbocations are intermediates and rearrangements occur
3. The mechanism for primary ROH is E2
4. The zaitsev rule is followed

Question 2

Dehydration to form Alkenes (using POCL3 and pyridine)

Answer 2

1. The mechanism is E2

2. No carbocation rearrangements occur

Question 3

Reaction with HX to form RX

Answer 3

1. Order of reactivity: R3COH>R2CHOH>RCH2OH
2. The mechanism for secondary and tertiary ROH is SN1: carbocations are intermediates and rearrangements occur
3. The mechanism for CH3OH and primary ROH is SN2

Question 4

Reaction with other reagents to form RX (SOCl2 and pyridine or PBr3)

Answer 4

1. Reactions occur with CH3OH and primary and secondary ROH

2. The reactions follow an SN2 mechanism

Question 5

Reaction with tosyl chloride to form alkyl tosylates

Answer 5

1. The C-O bond is not broken, so the configuration at a stereogenic center is retained.