Chapter 5, Problem 5.17P

Interpretation Introduction

Interpretation:

Structural formulas for all alkenes with the molecular formula $C_5{H}_{10}$ have to be drawn and named where alkenes with cis and trans isomers should be taken separately.

Concept Introduction:

IUPAC nomenclature:

• • Name the main chain: Find the longest carbon chain and name the chain according to the number of carbon atoms it contains; is also the root name.
• • Number the carbon atoms in the main chain: The carbons are numbered, in which the substituents must get lowest possible numbers.
• • Identify the substituents, and number each: The number at where substituents are present has to be noted. The substituents written as prefix.
• • Write the names as a single word: Use the hyphen to separate the numbers from the different prefix; commas to separate numbers. If two or more different substituents are present, arrange them in alphabetical order. If two or more identical substituents are present, use prefixes di-, tri-, tetra-, but this particular prefix should not be used for alphabetizing purpose.

Alkene: Unsaturated hydrocarbons having at least one double bond between two carbon atoms are known as alkenes.

The systematic name of alkenes are written by replacing “ane” of alkane with the suffix name “ene”. Numbering of the main chain should be in such away that alkene group must get lowest possible numbers.

Trans configuration: In trans configuration, groups present in the main chain are placed on opposite sides of the carbon-carbon double bond.

Cis configuration: In cis configuration, groups present in the main chain are placed on same sides of the carbon-carbon double bond.