The idea of working backwards from final target molecule to starting materials (usually via one or more intermediates) when designing a synthesis.
The development of this thought process is widely attributed to E. Corey of Harvard University, who was awarded the 1990 Nobel Prize in Chemistry.
This can be one of the most intimidating exercises because the products and reactant can look so different from each other it would seem at first glance its not possible to figure it out.
But here at Study Orgo, we work to bring you clear explanations and clear-cut explanations to tackle many organic chemistry reactions and synthesis questions you will see in Orgo1 and Orgo2.
We could think of forming an alkene from 3,3 dmethylbutanol by performing another E2 elimination (or dehydration) to remove the alcohol and anti-periplanar proton which would form 3,3-dimethylbutene.
Organic Chemistry Retrosynthesis
In the forward reaction, we can do this by activating the alcohol with tosyl chlroide to make a very good leaving group and then reacting with a strong base such as potassium tert-butoxide (t-Bu OK) to form the alkene. A three step synthesis from the alkyne product from a starting alcohol using reactions that are typically covered in the first few weeks of class.Universität Regensburg - Format: PDF Retrosynthesis Notes and examples Retrosynthesis Tutorial Organic Synthesis and Carbon-Carbon Bond Forming Reactions Retrosynthetic Analysis Lecture notes - Format: PDF Retrosynthetic Analysis An introduction - Format: PDF Retrosynthetic Analysis Strategies in synthetic planning - Format: PDF Retrosynthetic Analysis Advanced organic chemistry tutorial - Format: PDF Retrosynthetic Analysis Exercises in basic disconnections - Format: PDF Retrosynthetic Analysis An introduction - Format: PDF Retrosynthetic Analysis An introduction - Format: PDF Retrosynthetic Analysis Strategy of synthesis - Format: PDF Retrosynthetic Analysis and Synthetic Planning Basics - Format: PDF Solutions Manual Some examples - Format: PDF Strategies in Synthetic Planning Modern Stylistic Points in Retrosynthetic Analysis - Format: PDF Weighted Graphs Retrosynthetic analysis via weighted graphs - Format: PDF 2-Methyl-1-propanol. Professors often begin to expect students to perform synthesis (reactant to product) or retrosynthesis (product back to available reactants) on the exam.” The first step is to see which bonds have changed between the products and reactants and we can see the bond colored in red.Since only one bond changed, this is relatively “easy” example.The actual synthesis can then be designed based on the retrosynthetic analysis.The method of retrosynthetic analysis is very effective, but it requires a great knowledge of chemical compounds, classes of compounds, chemical reactions, reaction conditions etc.” Remembering E2 reaction mechanisms, any neighboring anti-periplanar proton and Br (leaving group) can be eliminate with a strong base to form a new pi bond.In the case of the alkyne, we would need two leaving groups and two rounds of elimination to form an alkyne.CMBI Advanced Retrosynthesis Lecture notes Disconnection Approach Introduction to chemical synthesis - Format: PDF Putting Reactions Together Synthesis and Retrosynthesis.Arizona State University, USA - Format: PDF Retrosynthesis The synthetic route to a target molecule: definitions and terms - Format: PDF Retrosynthesis Tutorial: Advanced Organic Chemistry - Format: PDF Retrosynthesis Lecture notes: designing organic syntheses.