Question

how to differentiate between SN1 and E1 reaction and SN2 and E2 reactions. Also what is the mechanism of SNar ,SNi reaction ​

Answer 1

Answer:

The “big barrier” to the SN1 and E1 reactions is carbocation stability. The rate of SN1 and E1 reactions proceeds in the order tertiary > secondary > primary. The E2 reaction has no “big barrier”, per se (although later we will have to worry about the stereochemistry

Explanation:

Answer 2

Explanation:

Differentiating between SN1/SN2/E1/E2 might seem a little confusing at first, but once you practice enough and get used to the nucleophiles and bases, you will be able to predict the products easily.

The first thing that you should take note of is the nucleophile/base. It is true that all nucleophiles are bases. They both donate a pair of electrons. However a nucleophile attacks a electrophile, whereas a base attacks a proton. You can use the table below to get used to some of the commonly used nucleophiles and bases:

First, look at the nucleophile/base and decide whether it acts as a nucleophile only or base only or a strong or weak nucleophile and base. Once you decide where it belongs, you can narrow down your choices to either substitution or elimination or in some cases both. To further boil down the choices, look at the substrate based on whether the substrate is primary, secondary or tertiary, you should be able to tell which reactions take place.

If you are asked the regioselectivity and stereoselectivity of the product, make sure you follow the rules of each reaction. A single reaction can give more than just one product. You must draw all the products with proper regiochemistry and stereochemistry