Question

1. Give the IUPAC name of the following compounds. a) PhCH2CH2COOH b) CHCHCH(CHs)CO2H c) CH3CH(CH3)CHBrCOOH d) HOOCCH2CH(CH3)CH3 e) CH3CH2CH(CH3)COONa ) (CH3)2C CHCOOH COOH NO2 g) COOH
Please do g and h only

Answer 1

Structure IUPAC name Home R.COOH R COOH (1R,2R)-2-methylcyclopentane-1-carboxylic acid COOH ONI NO2 (h) 2,4,6-trinitrobenzoic acid NO,

IUPAC nomenclature-

Molecule (g): (1R,2R)-2-methylcyclopentane-1-carboxylic acid

• Parent chain: The cyclopentane ring is the longest carbon chain, so it is identified as the parent chain.

• One Functional group present: -COOH group

  One alkyl group is present: -CH₃ group

  Priority: -COOH > -CH₃ group

• Numbering of the Carbon atoms: According to the priority order, the carbon atom attached to the functional group (-COOH group) is assigned number 1 and the carbon atom attached to the methyl group is assigned number 2 and then the subsequent carbon atoms are numbered.

  The name of the functional group or the substituent will be written after the assigned number, separated by a dash.

• The carbon 1 and the carbon 2 are chiral in nature, since four different groups are attached to it.

  The Carbon 1 is assigned the R- configuration and the Carbon 2 is also assigned R- configuration.

  Rules for assigning the R- and S- Configuration:

  a. The groups attached to the chiral carbon atom are assigned numbers; the group with higher mass number is given more priority and assigned the smallest number.

  b. The group with the lowest priority is visualized below the plane and the group with the highest priority is visualized above the plane.

  c. Now, an arrow is drawn from the group with the highest priority to the group with the second highest priority and then to the group with the third highest priority. If the direction of the arrow is clockwise, then the chiral carbon is always assigned R- configuration and if the direction of the arrow is anticlockwise, then the chiral carbon is always assigned S- configuration.

Molecule (h): 2,4,6-trinitrobenzoic acid

• Parent chain: The benzene ring is the longest carbon chain, so it is identified as the parent chain.

• Functional groups present: -COOH group and 3 -NO₂ groups.

  Priority : -COOH > -NO₂

• Numbering of the Carbon atoms: The carbon atom attached to the -COOH group is assigned the number 1. As the same -NO₂ functional group is present more than once in this molecule; the number of the carbon atoms to which the -NO₂ groups are attached are assigned the number 2, 4 and 6. Also, there are three -NO₂ groups present, so tri- prefix is used. The name of the functional group will be written after the number assigned to it, separated by a dash.