Lesson Plan | Lesson Plan Tradisional | Organic Functions: Organic Anhydride Nomenclature

Objectives

Duration: (10 - 15 minutes)

The purpose of this stage is to give students a solid understanding of organic anhydrides, with a focus on IUPAC nomenclature, so they can accurately name and identify these compounds. This comprehension is essential for them to distinguish the nomenclature of organic anhydrides from other organic compounds, providing a crucial foundation for advanced studies in Organic Chemistry.

Objectives Utama:

1. Clarify the definition and structure of organic anhydrides.

2. Instruct on the correct IUPAC nomenclature for organic anhydrides.

3. Differentiate the nomenclature of organic anhydrides from other organic compounds.

Introduction

Duration: (10 - 15 minutes)

The aim of this stage is to equip students with a solid and practical understanding of organic anhydrides, with an emphasis on IUPAC nomenclature, ensuring they know how to correctly identify and name these compounds. Such understanding is crucial for distinguishing the nomenclature of organic anhydrides from other organic compounds, serving as a foundational step for Advanced Organic Chemistry.

Did you know?

Did you know that organic anhydrides are used extensively in the plastics and polymers sector? For example, maleic anhydride is a key intermediate in making polyester resins and curing agents for epoxies. Additionally, some anhydrides, such as acetic anhydride, are involved in the production of pharmaceuticals like aspirin! This highlights how these compounds are part of our everyday lives, even if we don't realize it.

Contextualization

Kick off the lesson by explaining that organic anhydrides are chemical compounds that come from carboxylic acids through the removal of a water molecule between two acid molecules. This type of functionality plays a significant role in various organic reactions, including the creation of esters and amides. Emphasize that grasping the nomenclature of these compounds is vital for effective communication in organic chemistry and for understanding more complex chemical reactions.

Concepts

Duration: (40 - 50 minutes)

This stage aims to provide a thorough and practical understanding of organic anhydrides and their naming conventions. By addressing key topics related to definition, structure, and IUPAC nomenclature rules, along with solving practical questions, students will learn to effectively recognize and name organic anhydrides, differentiating them from other compounds, which is essential for advanced studies in Organic Chemistry.

Relevant Topics

1. Definition and Structure of Organic Anhydrides: Explain that organic anhydrides result from the dehydration of two carboxylic acids, forming an anhydride bond (R-CO-O-CO-R). Provide details about the general structure and functional groups involved.

2. IUPAC Nomenclature of Organic Anhydrides: Introduce the IUPAC rules for naming anhydrides. Explain that the nomenclature is derived from the original carboxylic acids. For instance, an anhydride formed from two acetic acids is referred to as acetic anhydride. In the case of mixed anhydrides, name the acids alphabetically.

3. Practical Examples and Comparisons: Offer examples of common organic anhydrides (like acetic anhydride, benzoic anhydride, etc.) and draw comparisons to carboxylic acids and esters, spotlighting the differences in structure and naming conventions.

To Reinforce Learning

1. What is the name of the anhydride derived from formic acid and acetic acid?

2. What would the anhydride formed from propanoic acid and butanoic acid be called?

3. What are the structural and nomenclature differences between acetic anhydride and ethyl acetate?

Feedback

Duration: (25 - 30 minutes)

This stage seeks to review and consolidate the knowledge students have gained about the nomenclature of organic anhydrides. By discussing their questions and encouraging further reflection, the goal is to ensure students fully grasp the material, can apply it to various contexts, and are ready to tackle more complex challenges in Organic Chemistry.

Diskusi Concepts

1. 📍 What is the anhydride derived from formic acid and acetic acid? 2. The anhydride formed from formic acid (methanoic acid) and acetic acid (ethanoic acid) is known as methanoic-ethanoic anhydride. In IUPAC terms, mixed anhydrides list the names of the originating acids in alphabetical order, followed by 'anhydride'. 3. 📍 How would the anhydride from propanoic acid and butanoic acid be named? 4. The anhydride formed from propanoic acid (propanoic acid) and butanoic acid (butanoic acid) is called butanoic-propanoic anhydride. Again, the acid names are listed alphabetically. 5. 📍 What are the structural and nomenclature differences between acetic anhydride and ethyl acetate? 6. Structurally, acetic anhydride (ethanoic anhydride) has the formula (CH₃CO)₂O, with two acetic acid units linked by an oxygen atom, creating an anhydride bond. Conversely, ethyl acetate has the formula CH₃COOCH₂CH₃, where the acyl group (CH₃CO-) from acetic acid is bonded to an ethyl group (CH₂CH₃). 7. In nomenclature, the anhydride name reflects the originating carboxylic acids, while the ester name starts with the alkyl group (ethyl), followed by the name of the acid with the 'ate' ending (acetate).

Engaging Students

1. 📝 Reflective Questions: 2. How do organic anhydrides affect the reactivity of a molecule in chemical reactions? 3. What real-world applications do organic anhydrides have in the pharmaceutical industry? 4. Discuss how the IUPAC nomenclature for organic anhydrides can help avoid confusion in scientific literature. 5. For an anhydride formed from benzoic acid and acetic acid, what would the correct name be according to IUPAC and why? 6. Why is it important to differentiate the nomenclature of organic anhydrides from other compounds, such as esters and carboxylic acids?

Conclusion

Duration: (10 - 15 minutes)

The aim of this stage is to review and solidify the understanding students have gained during the lesson. By recapping key points, linking theory to practice, and emphasizing the topic's relevance, this stage ensures students have a clear and interconnected grasp of the content, preparing them for more complex applications.

Summary

['Definition and structure of organic anhydrides.', 'IUPAC rules for naming organic anhydrides.', 'Structural and nomenclature differences between anhydrides and other compounds, like esters.', 'Practical examples of common organic anhydrides and their respective nomenclature.']

Connection

The lesson effectively connected theory with practice by presenting concrete examples of organic anhydrides and their respective naming conventions, along with a discussion of their applications in industry and pharmaceuticals. Problem-solving and comparisons with other compounds reinforced the practical understanding of the theoretical material.

Theme Relevance

The topic's significance is underscored by the widespread use of organic anhydrides in various sectors, including plastics, polymers, and pharmaceuticals. Interesting facts, such as their role in producing polyester resins and synthesizing medications like aspirin, illustrate how these compounds feature in daily life, often without us realizing it.