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General organic chemistry

Keynotes in Organic Chemistry

Excellent book for general organic chemistry. I found this book particularly useful for first year chemistry at Oxford. Provides useful summary of most of the fisrt year topics in organic chemistry, and is good for preparing written answers to descriptive questions.
Oxford Chemistry Primers

Written by Oxford lecturers, these books are excellent for learning any organic topic in detail.
Organic Chemistry

Essential book for any Undergraduate Chemist.

Specific topics

An Introduction to Free-radical Chemistry

Very good book for free radicals.
Organic Synthesis: The Disconnection Approach

Excellent for retrosynthetic analysis.