Concept: Intro to Predict the Product1m
Now we're going to do some predict the product practice problems involving all the different reactions that organometallics can undergo. Keep in mind that some of these reactions, will be multiple step reactions. So what that means is that you may have to draw back from previous lessons in order to really figure out the entire thing.
At the end, just like always, I'll explain the answers to every problem. Let's go ahead and begin with problem one.
Concept: Intro to Retrosynthesis1m
Now let's focus on some practice problems involving organometallics, but going the other way around. We want to do some retro-synthesis now. What that means is you're going to try to figure out what reagents it's going to take to make the final product. Think about all of the different reactions of organometallics we talked about and see how you can use them to your advantage in the next few questions.
Let's go ahead and try to do the first one.
Problem: Propose a synthesis to accomplish the following transformation5m
Problem: Propose a synthesis to accomplish the following transformation7m
Problem: Predict the product of the reaction8m
In each reaction box, place the best reagent and conditions from the list below.
Show how the following compounds could be synthesized from cyclohexanol.
Suggest the most appropriate method for each of the following laboratory syntheses. In each case, suggest both a chromium reagent and a chromium-free reagent.
Predict the organic product(s) of the following reaction. When appropriate, be sure to indicate stereochemistry. If more than one product is formed be sure to indicate the major product, if stereoisomers are produced in the reaction be sure to indicate the relationship between them. Draw all answers in skeletal form.
Predict the organic product(s) for the following reaction. Be sure to indicate stereochemistry when appropriate. If stereoisomers are produced draw one and state the relationship between the otherstereoisomer formed. (enantiomers, diastereomers, etc.).
Provide the reagents or starting materials to perform the indicated transformations. More than one reaction may be required. Be sure to number your steps if it is important for the synthetic transformation to take place.
Propose a sequence of synthetic steps that would efficiently accomplish the conversion shown below. Show all starting materials and necessary reagents, but do not give mechanisms.
Provide a synthesis of the following alcohol. All of the carbons in the molecule below must come from cyclopentane. You may use any other reagents that you find necessary.
Provide a synthesis of the following compound; starting from the indicated materials for the source of carbon atoms in the target. You may use any other reagents that you find necessary.
Provide the reagent or starting material to perform the indicated transformation. More than one reaction may be required. You should number your steps if it is important for the synthetic transformation to take place.
Predict the missing structures of products or reagents that you may use to accomplish the following transformations. Show the source of incorporation of deuterium and the stereochemistry when appropriate (No mechanism is required).
Provide the reagents necessary for the following conversion.
a) 1. CH3CH2MgBr/ether, 2. H3O+, Δ
b) 1. NaBH4/CH3OH, 2. CH3CH2MgBr
c) 1. H3O+ , CH3CH2MgBr/ether
Provide the reagents to accomplish the following transformations. More than one step might be required for each transformation.
This is a synthesis question. You need to show how the starting material can be converted into the product(s) shown. You may use any reactions you have learned. Show all the reagents you need. Show each molecule synthesized along the way and be sure to pay attention to the regiochemistry and stereochemistry preferences for each reaction. If you make a racemic mixture, you can either draw both enantiomers or simply draw one structure and label all chiral centers with an asterisk (*). Either way, you must write racemic if appropriate.
All of the carbon atoms of the products must come from the starting materials.