Ch. 15 - An Introduction to Organometallic CompoundsWorksheetSee all chapters
All Chapters
Ch.1 - Covalent Bonding and Shapes of Molecules
Ch.2 - Alkanes and Cycloalkanes
Ch.3 - Stereoisomerism and Chirality
Ch.4 - Acids and Bases
Ch.5 + 6 - Alkenes and Reactions of Alkenes
Ch.7 - Alkynes
Ch.8 - Haloalkanes, Halogenation and Radicals
Ch.9 - Nucleophilic Substitution (Part 1)
Ch.9 - b-Elimination (Part 2)
Ch.10 - Alcohols
Ch.11 - Ethers, Epoxides and Sulfides
Bonus Chapter: Synthesis
Ch. 12 - Infrared Spectroscopy
Ch. 13 - Nuclear Magnetic Resonance
Ch. 14 - Mass Spectrometry
Ch. 15 - An Introduction to Organometallic Compounds
Ch. 16 - Aldehydes and Ketones
Ch. 17 - Carboxylic Acids
Ch. 18 - Functional Derivatives of Carboxylic Acids
Ch. 19 - Enolate Anions and Enamines
Ch. 20 - Dienes, Conjugated Systems, and Pericyclic Reactions
Ch. 21 - Benzene and the Concept of Aromaticity
Ch. 22- Reactions of Benzene and Its Derivatives
Ch. 23 - Amines
Ch. 25 - Carbohydrates
Ch. 27 - Amino Acids and Proteins

Cyclopropanation is the general name for a series of reactions that all produce very similar products by different mechanisms. You may be responsible for one or more of these reactions on your exam, so let’s get into them.

Concept #1: General properties of cyclopropanation.      

Concept #2: Reaction with a simple carbene.

Concept #3: Reaction with chloroform (CHCl3) and tert-butoxide.

Concept #4: Reaction with diazomethane and light or heat.

Concept #5: The Simmons-Smith reaction.

You should not be responsible for the full mechanism of Simmons-Smith, but you should know what the reagents are, and be able to predict that it is a form of cyclopropanation. 

Additional Problems
How many atoms and electrons are directly involved in the bond-making and bond-breaking of the reaction given below?  Choose the right answer.  Addition of dichlorocarbene (CCl2) to propene a) four atoms, two electrons b) four atoms, three electrons c) four atoms, four electrons d) three atoms, two electrons e) three atoms, three electrons f) three atoms, four electrons
Provide either the reagent(s) or the product(s) for the reaction below. This is not a mechanism question. Simply write the answer in the box.
The creation of a cyclopropane ring from alkenes can be accomplished by two different methods. 
The creation of a cyclopropane ring from alkenes can be accomplished by two different methods. 
Give the product, or products, including stereochemistry of the reaction of (Z)-3-methyl-2-pentene with the reagent below. If the products are a pair of enantiomers, you need to draw only one and state that the other enantiomer is formed.  CHCl3, NaOH
Predict the principal organic product of each of the following reactions: 
Insert the missing curved-arrows for the following two reaction transformation. Include all missing curved arrows.
Consider the strucutres below and answer the following questions.  f. Which disubstituted alkene forms enantiomeric pairs on treatment with CHCl 3 / NaOH?
Predict the products of the following reaction. Show stereochemistry when applicable.   
Heating diazomethane generates nitrogen gas and a carbene. This question pertains to the structure and reactivity of the carbene species. a) Draw a picture describing the geometry of the carbene that is generated, showing any orbitals that contain lone pairs or are empty.   b) On your picture from part a, indicate the types of orbitals that are present (s, p, sp 3, etc).   c) On your picture from part a, indicate in which orbital the lone pair resides.   d) On your picture from part a, identify any orbitals having nucleophilic character. Do the same for orbitals with electrophilic character.    
Synthesis: Provide the reagents for the following conversions.  Note that some transformations may require more than one chemical step. e.g. the acid step of a Grignard  reaction. For full credit, you must include and number these steps when necessary.
Supply the missing reagents for the following transformation. 
What is the product of the reaction shown?
Predict the product of the following reaction. Show stereochemistry when applicable.   
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.
Propose a mechanism for the following reaction.
Show the appropriate arrow pushing on the left side of the equation and write the structure after the first immediate step on the right side. (please re-write the reagent where necessary)
Draw the major expected product of the following reaction. Clearly show stereochemistry in the product by drawing one wedged bond, one hashed bond and two in-plane bonds per stereocenter.