TATA NAMA ASAM ALKANOAT ASAM KARBOKSILAT | SENYAWA TURUNAN ALKANA

Summary

This script provides a comprehensive guide to the naming conventions of alkanoic acids (carboxylic acids) using both IUPAC and trivial systems. It explains the step-by-step process of IUPAC nomenclature, from identifying the longest carbon chain to numbering carbons, naming alkyl branches, and using prefixes for multiple branches. The script also delves into common trivial names based on historical or natural sources, with examples such as formic acid and acetic acid. Through practical examples and clear explanations, the script makes understanding the systematic approach to naming carboxylic acids accessible and straightforward.

Takeaways

• 😀 Alkanoic acids, or carboxylic acids, are derivatives of alkanes with the general formula CₙH₂ₙ₊₂O₂ and contain a carboxyl functional group (-COOH).
• 😀 IUPAC naming for alkanoic acids involves selecting the longest carbon chain containing the carboxyl group and modifying its name to end in '-oic acid'.
• 😀 The numbering of the parent chain starts from the carbon attached to the carboxyl group, which is always assigned the number 1.
• 😀 Alkyl branches on the parent chain are named as in other alkane derivatives, with common groups including methyl (CH₃), ethyl (C₂H₅), etc.
• 😀 If there are multiple identical branches, prefixes such as di-, tri-, and tetra- are used (e.g., dimethyl, trimethyl).
• 😀 The final IUPAC name is written by placing 'acid' at the end of the name, preceded by the position and name of any alkyl branches.
• 😀 Trivial names of alkanoic acids are based on historical or natural sources, such as 'formic acid' (from ants) and 'acetic acid' (from vinegar).
• 😀 The trivial naming system uses Greek letters (alpha, beta, gamma, etc.) to number carbons in the parent chain, starting from the second carbon as 'alpha'.
• 😀 The IUPAC and trivial naming systems share the structure of placing 'acid' at the end but differ in how the parent chain and substituents are named.
• 😀 In complex molecules with multiple substituents, branches are listed alphabetically (e.g., 'ethyl' before 'methyl') in both IUPAC and trivial names.

Q & A

What are carboxylic acids (asam alkanoat) and what is their general formula?

Carboxylic acids (asam alkanoat) are organic compounds derived from alkane hydrocarbons. Their general formula is CnH2n+1COOH, where the COOH group is the functional group known as the carboxyl group.

How is the IUPAC name for a carboxylic acid determined?

The IUPAC name for a carboxylic acid is determined by identifying the longest carbon chain that contains the carboxyl group (COOH). The base name is derived from the alkane name, replacing the '-ane' suffix with '-oic acid'. The chain is numbered such that the carboxyl group is on carbon 1, and substituents or branches are named and numbered accordingly.

What is the first step in naming a carboxylic acid using the IUPAC system?

The first step is to determine the longest carbon chain that contains the carboxyl group (COOH), which becomes the parent chain. This chain is then named based on its length, with the '-ane' ending of the alkane name replaced by '-oic acid'.

How are substituent groups named and numbered in carboxylic acids?

Substituent groups, such as alkyl groups (e.g., methyl, ethyl), are named based on the number of carbon atoms they contain. The chain is numbered starting from the carboxyl group, and substituents are positioned by their carbon number on the parent chain. If multiple identical substituents are present, prefixes like 'di-', 'tri-', 'tetra-' are used.

What is the naming rule for a carboxylic acid with both a hydroxyl group and a methyl group as substituents?

The hydroxyl group (-OH) and methyl group (CH3) are named and positioned according to their locations on the parent chain. The hydroxyl group is named first when ordering alphabetically, and the parent name is adjusted to reflect the positions of the substituents, for example, '2-hydroxy-2-methylbutanoic acid'.

What is the rule for writing the name of a carboxylic acid when there are multiple substituents?

When multiple substituents are present, their names are listed alphabetically, and the positions are indicated by numbers. The base name of the acid is always placed at the end, and the substituents are ordered according to their alphabetical order regardless of their position numbers.

What are some examples of trivial names for carboxylic acids?

Trivial names for carboxylic acids often come from historical or natural sources. Examples include 'formic acid' (HCOOH), derived from the Latin word for ant (formica), 'acetic acid' (CH3COOH), derived from vinegar (acetum), and 'butyric acid' (C4H8O2), derived from butter (butyrum).

How is the trivial naming system different from the IUPAC system?

The trivial naming system for carboxylic acids is based on historical or common names rather than strict structural rules. Unlike IUPAC names, which follow a systematic approach based on molecular structure, trivial names are often simpler and have roots in the natural sources or discovery of the compound.

How are carboxylic acids numbered in the trivial naming system?

In the trivial naming system, carboxylic acids are numbered using Greek letters starting from the carbon adjacent to the carboxyl group. The carbon directly attached to the carboxyl group is not numbered, while the next carbons are designated as alpha (α), beta (β), gamma (γ), etc.

Can you give an example of how to name a carboxylic acid with both methyl and ethyl groups using the trivial system?

In the trivial naming system, if a carboxylic acid has both methyl and ethyl groups, their positions are labeled using Greek letters. For example, in 'beta-ethyl-alpha, teta-dimethylheptanoic acid', the methyl groups are located on the alpha and teta carbons, while the ethyl group is on the beta carbon. The substituents are listed alphabetically, with 'ethyl' coming before 'dimethyl'.