Chapter 6.15, Problem 53P

(a)

Interpretation Introduction

Interpretation:

The major product obtained from the given reaction should be identified.

Concept introduction:

Addition Reaction: It is defined as chemical reaction in which two given molecules combines and forms product. The types of addition reactions are electrophilic addition, nucleophilic addition, free radical additions and cycloadditions. Generally, compounds with carbon-hetero atom bonds favors addition reaction.

In addition reaction of alkenes when two substituents are placed on same side of $C=C$ then it is named as $syn$ addition if it is placed on opposite sides of $C=C$ it is defined as anti-addition.

Regioselective reaction: They are reactions which contain more than one product which are actually molecules with same molecular formula but different in the way they are connected and among those products only one product is major.

The reaction is considered as regioselective if it gives rise to specific constitutional isomer.

Constitutional Isomers: Two compounds are considered as constitutional isomers if they have same molecular formula but different in their connectivity.

(b)

Interpretation Introduction

Interpretation:

The stereo isomers formed in the given reaction should be determined.

Concept introduction:

Stereo selective: The reaction is considered as stereo selective if it gives rise to only specific stereo isomer.

Stereo specific: The reaction is considered as stereo specific if the reactant is stereo isomers that give rise to different set of stereo isomers.

Stereoisomers: Two compounds with same molecular formula but different in their orientation are considered as isomers.

E configuration: The geometric isomers are given E configuration if high priority groups are placed on opposite sides of the bond.

Z configuration: The geometric isomers are given Z configuration if high priority groups are placed on same sides of the bond.

$Erythro$ Product: It is the representation of carbohydrates in Fischer projection when two same substituents are placed on the same side.

$Threo$ Product: It is the representation of carbohydrates in Fischer projection when two same substituents are placed on opposite side.

R and S nomenclature: it is used to assign the molecule using CIP rules.

The CIP rules are as follows:

Select the chiral carbon and assign the numbers according to the decreasing atomic mass of atoms attached to it.

If the numbering follows clockwise direction then the molecule is termed as R and if it follows anti-clockwise direction then molecule is termed as S.