Question

The IUPAC name of product (B) is (a) Heptane-2, 6 -dione (b) 6 -oxoheptanoic acid (c) 5 -oxohexanal (d) 6 -oxoheptanal

Short answer

Answer: (b) 6 -oxoheptanoic acid

Step-by-step solution

Identify the name from the given options

First, let's identify product B by matching the given options with the IUPAC name of product B. (a) Heptane-2, 6 -dione - A 7- carbon chain with ketone groups on carbons 2 and 6. (b) 6 -oxoheptanoic acid - A 7-carbon chain with a carboxylic acid on carbon 7 and a ketone group on carbon 6. (c) 5 -oxohexanal - A 6-carbon chain with an aldehyde group on carbon 1 and a ketone group on carbon 5. (d) 6 -oxoheptanal - A 7-carbon chain with an aldehyde group on carbon 1 and a ketone group on carbon 6. Now, let's analyze these options to identify the correct name for product B.

Analyze the options based on rules of IUPAC nomenclature

We should consider two rules to determine the correct IUPAC name: The positions of functional groups on the chain and the priority of functional groups. The options given have two functional groups - ketone and aldehyde/carboxylic acid. The priority order is: carboxylic acid > aldehyde > ketone, based on IUPAC rules. (a) Heptane-2, 6 -dione - This name indicates a ketone on carbons 2 and 6 but is missing any higher-priority functional groups. (b) 6 -oxoheptanoic acid - There's a carboxylic acid terminus and a ketone group on carbon 6. Since the carboxylic acid functional group has the highest priority, this could be the correct name. (c) 5 -oxohexanal - There's an aldehyde group on carbon 1 and a ketone group on carbon 5. The aldehyde group is higher in priority than the ketone, making this another possibility. (d) 6 -oxoheptanal - This name indicates an aldehyde group on carbon 1 and a ketone group on carbon 6. Based on functional group priorities, it is also a potential candidate.

Determine the correct IUPAC name based on the positions of functional groups

Considering the priority of functional groups and their positions on the chain, we can eliminate option (a) because it only contains ketone functional groups. Now, let's examine the remaining options: (b) 6 -oxoheptanoic acid: the carboxylic acid terminal and ketone group on carbon 6. (c) 5 -oxohexanal: a 6-carbon chain with an aldehyde at carbon 1 and ketone group carbon 5. (d) 6 -oxoheptanal: a 7-carbon chain with an aldehyde at carbon 1 and ketone group on carbon 6. Since the ketone group on carbon 6 is part of the root name in option (b), the IUPAC name would be written as 6 -oxoheptanoic acid. Therefore, the correct IUPAC name for product B is: (b) 6 -oxoheptanoic acid

Key concepts

Understanding Organic Chemistry

Organic chemistry is the study of the structure, properties, composition, reactions, and synthesis of organic compounds that contain carbon atoms. These compounds form the basis of all life on Earth and encompass a vast array of substances, including plastics, pharmaceuticals, and dyes, to name a few.

What makes organic chemistry unique and diverse is the ability of carbon atoms to form stable bonds with other carbon atoms, creating long and complex chains and rings of carbons, as well as bonding with other elements like hydrogen, oxygen, nitrogen, and more. The carbon-hydrogen bond is a basic unit in organic molecules, designated as hydrocarbons, from which more complex structures can derive through the addition or substitution of other atoms or groups of atoms - known in chemistry as functional groups.

In essence, understanding organic chemistry not only involves memorizing structures and reactions but also develops one's skill in reasoning and visualizing how atoms interact and combine to form the myriad of compounds that characterize organic chemistry's breadth.

The Role of Functional Groups in Organic Chemistry

Functional groups are specific groups of atoms within molecules that are responsible for the characteristic chemical reactions of those molecules. They are the reactive parts of the molecule and dictate how a compound will react with others. In the vast family of organic compounds, it is the functional groups that determine the primary properties and reactivity.

Common functional groups include hydroxyl (alcohol), carboxyl (carboxylic acid), amino (amines), and carbonyl (which includes aldehydes and ketones). Each has a specific and consistent pattern of reactivity. For example, alcohols generally can be dehydrated to form alkenes, carboxylic acids can react to form esters, and amines are basic and react with acids to form amides. Knowing these groups is vital for predicting and understanding the behaviors of organic compounds.

The presence of these functional groups within a compound also guides the nomenclature, as they often have to be indicated in the name of the compound due to their significance in its chemical reactivity and properties.

Priority Order of Functional Groups in IUPAC Nomenclature

The International Union of Pure and Applied Chemistry (IUPAC) developed a system to name organic chemical compounds to provide a clear and standardized method for naming complex organic molecules. This system takes into account the types of atoms present, the arrangement of the atoms, and the functional groups attached to those atoms.

A crucial aspect of this nomenclature is the priority order of functional groups, which reflects their relative importance when naming a compound with multiple functional groups. The priority determines which group is selected as the primary functional group, influencing the root name of the compound and the prefixes or suffixes used.

According to IUPAC nomenclature, the priority order from highest to lowest is: carboxylic acids, anhydrides, esters, amides, aldehydes, ketones, alcohols, amines, ethers, alkynes, and alkenes, among others. When naming compounds, the highest priority group gets the suffix, and other groups are named with prefixes, showing both their nature and location on the carbon chain. For example, in naming '6-oxoheptanoic acid', the 'oic acid' suffix identifies the molecule as a carboxylic acid, which takes precedence over the ketone indicated by the 'oxo-' prefix.