Week_3.3_PurpleBook_Answers - 71 Making Alcohols into...

Info iconThis preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
OH Cl OH Cl OH OH Making Alcohols into Leaving Groups 1. The OH from an alcohol is not a good leaving group. Why? One way of making it a good leaving group is to protonate it. This often creates problems with carbocations, rearrangements, etc. It can be used in limited cases: 2. Provide curved-arrow mechanisms for the following transformations: The best ways of turning alcohols into leaving groups (at least for S N 2 reactions) are to use either SOCl 2 or to form a "tosylate": 3. Provide the intermediates and products in the following synthetic sequences. Watch stereochemistry ! SOCl 2 , pyridine OH 2 TsCl, pyridine OH 2 OH is a very strong base and strong bases make poor leaving groups. + + Cl OTs CN CN + HCl HCl NaCN NaCN H + :Cl H + SN1 SN2 Cl: Week 3 71
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
OH Cl OTs Br S Cl O O CH 3 R O 2 S Cl O S H O O R O S O O R S Cl O Cl OH OH O S H O Cl O S O Cl Making Alcohols into Leaving Groups: Mechanisms 1. Provide a complete curved-arrow mechanism for each of the following transformations. Be sure to pay attention to stereochemistry! P
Background image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 05/01/2008 for the course CHEM 51 taught by Professor Gribble during the Spring '08 term at Dartmouth.

Page1 / 8

Week_3.3_PurpleBook_Answers - 71 Making Alcohols into...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online