Basics of E1
Mechanism Steps
Reaction Conditions
Carbocations
Products & Rearrangements
100

What does the "E" in E1 stand for?

Elimination

100

What happens first in an E1 reaction?

The leaving group leaves, forming a carbocation.

100

Does E1 require a strong or weak base?

Weak base

100

What makes a carbocation more stable?

More alkyl groups (like 3° > 2° > 1°)

100

What type of product is favored in E1: Zaitsev or Hofmann?

Zaitsev (more substituted alkene)

200

How many steps are in an E1 reaction?

Two

200

What happens in the second step of an E1 reaction?

A base removes a β-hydrogen to form a double bond.

200

What kind of solvent favors E1 reactions?

Polar protic solvent (like water or alcohol)

200

What rearrangement can happen to make a carbocation more stable?

Hydride shift or methyl shift

200

Does E1 usually form one or multiple products?

It can form multiple, but the major one is usually Zaitse

300

What does the "1" in E1 refer to?

This means that the rate depends on one molecule.

300

What is the name of the intermediate formed in an E1 reaction?

Carbocation  

300

Which type of substrate is most likely to undergo E1: 1°, 2°, or 3°?

300

Why can rearrangement happen during an E1 reaction?

Because the carbocation can be rearranged to become more stable before elimination occurs.

300

How can you tell E1 occurred instead of SN1?

An alkene is formed instead of a substitution product.