Books

RedLectern topic

Organic Chemistry

Core ideas for representing carbon compounds, explaining their structures and reactions, and interpreting basic evidence about molecular structure.

For: Learners beginning organic chemistry, returning to it, or seeking a focused route into a core topic.

After this page you can: Represent simple organic molecules, identify common functional groups and stereochemical features, explain basic reaction steps, and use introductory spectra to support a structural proposal.

Page reviewed

Part of: Science › Chemistry

About Organic Chemistry

Organic chemistry is the study of carbon compounds. Carbon atoms can form four covalent bonds and bond to one another in chains and rings, creating a wide variety of molecular structures.

It is studied by representing molecules, relating their structures to functional groups, and tracing how bonds change in reactions. Learners can practice drawing structures, considering stereochemistry, and using spectroscopy to gather evidence about molecular structure.

Start here

route

I’m returning to the subject

Use the course outline to review structures, transformations, mechanisms, and stereochemical reasoning.

Start with: Organic Chemistry I

route

I have a specific goal: interpreting spectra

Begin with IR patterns, then compare what other common structure-determination techniques examine.

Start with: Interpreting Infrared Spectra

Learn the foundations

1.Molecular structure and bondingCarbon’s bonding and molecular geometry help explain the range of structures studied in organic chemistry.

Carbon’s bonding and molecular geometry help explain the range of structures studied in organic chemistry.

  • Organic Chemistry I

    The course introduces principles for understanding organic molecular structure and reactivity.

Covalent bond

A bond formed when an electron pair is shared between atoms.

Functional group

A group of atoms within a molecule that has characteristic chemical behavior.

Try it

Sketch a carbon atom with four single bonds, then draw a second carbon joined to it by one of those bonds.

Each carbon can have four covalent bonds; the two-carbon structure can be represented with a single bond between the carbon atoms.

2.Stereochemistry and molecular shapeStereochemistry considers how three-dimensional arrangement distinguishes molecules, including mirror-image forms.

Stereochemistry considers how three-dimensional arrangement distinguishes molecules, including mirror-image forms.

  • Organic Chemistry I syllabus

    The course objectives include using stereochemical considerations when analyzing mechanisms and transformations.

Chiral

A molecule is chiral if it is not identical to its mirror image.

Chirality center

A common chirality center is a tetrahedral carbon bonded to four different groups.

Try it

Does a tetrahedral carbon bonded to H, OH, CH3, and CH2CH3 have four different groups attached?

Yes. Those four groups differ, which is the common structural cause of chirality described for a tetrahedral carbon.

3.Reaction mechanisms and electron flowA reaction mechanism describes the stages of a chemical transformation, including the bonds broken and formed.

A reaction mechanism describes the stages of a chemical transformation, including the bonds broken and formed.

Reaction mechanism

A detailed description of what happens at each stage of a chemical transformation.

Homolytic cleavage

Bond cleavage in which one electron remains with each product fragment.

Try it

In a homolytic bond cleavage, how many electrons from the broken bond go to each fragment?

One electron goes to each product fragment.

4.Functional groups and reaction patternsFunctional groups classify molecules by characteristic chemical behavior and help organize reaction patterns.

Functional groups classify molecules by characteristic chemical behavior and help organize reaction patterns.

  • Organic Chemistry I

    The course includes substitution and elimination reactions, carbonyl chemistry, and aromatic compounds.

Alkene

An organic compound containing a carbon–carbon double bond.

Try it

Which functional group is present in a molecule with a C=C bond?

The C=C bond is the carbon–carbon double-bond functional group found in alkenes.

5.Spectroscopy and structure evidenceMass spectrometry, IR, and NMR are techniques of structure determination for organic molecules.

Mass spectrometry, IR, and NMR are techniques of structure determination for organic molecules.

Infrared spectroscopy

A technique that can provide structural information from characteristic functional-group absorption bands.

Try it

An IR spectrum has a strong, broad O–H absorption. Which kind of functional group could this support?

It could support the presence of an alcohol O–H group; an O–H absorption is listed among characteristic IR bands.

Latest

No recent updates are available.

See the sources list

Books

Glossary

Every free Organic Chemistry course and book on RedLectern

Free Organic Chemistry online courses

  1. Advanced Organic ChemistryMIT 5.43 · Browse materials
  2. Introduction to Organic Synthesis LaboratoryMIT 5.37 · Browse materials
  3. Organic Chemistry IMIT 5.12 · Browse materials
  4. Organic Chemistry IMIT 5.12 · Browse materials
  5. Organic Chemistry IIMIT 5.13 · Browse materials
  6. Synthetic Organic Chemistry IIMIT 5.512 · Browse materials
  7. Cosmic Origin of the Chemical ElementsMIT RES.8-007 · Open on OCW · Video
  8. Organic Chemistry IIMIT 5.13 · Open on OCW
How these courses are chosen

Listed as Organic Chemistry courses:

  • those whose title contains “Organic Chemistry”, or
  • those tagged “Organic Chemistry” as one of at most 2 topic tags, or as the first of 3.

Free Organic Chemistry textbooks and books

Show all 19 booksShow fewer books

Questions and comments