O chem exam 3.txt

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What are some strong Nucleophiles?
- NaOR
- RLi
- NaOH
- KOH
- NaCN
- KCN
- NaC=CR
- NaNH2
- NaNHR
- NaNR2
- NaI
- LiBr
- Ki
- NaN3
What are some examples of Weak Nucleophiles?
- ROH
- H2O
What kind of reaction does a Primary carbon favor?

Sn2
What kind of reaction does a Tertiary carbon favor?

Sn1
What kind of reaction does an Aprotic Polar solvent favor?

Sn2
What kind of run does a Protic polar solvent favor?

Sn1
What is a Polar Protic solvent?
- A solvent that con taints a H+ bonded to an O or N
- Contain a dissociable H and can donate the proton
What is a Polar Aprotic solvent?
- Do NOT contain a H bonded to an O or N
- Do NOT contain a dissociable H and cannot donate a proton
What are some examples of Polar Protic solvents?
- H2O
- ROH
- RNH2
- R2NH
What are some examples of Polar Aprtoic solvents?
- Acetone
- DMF
- HMPA
- DMSO
- Nitromethane
What is a Substrate?
- The electrophile in a substitution rxn
- The compound containing the LG
What are common LG's?

Halogens such as Cl Br and I
What is a Concerted process?

A process when the nucleohilic attack and the loss of the leaving group occur simultaneously
What is a Stepwise process?

A process when the loss of the leaving group occurs first followed by the nucleophilic attack
In an Sn2 run, when the reactant exhibits the S configuration and the product exhibits the R configuration what is the process called?

Inversion of configuration
What are substrate reactions?

Rxns that exchange one functional group for another
What is the electrophile?

The substrate, must contain a LG
What is the process in a Concerted Process?
- When the nucelohilic attack and loss of a LG occur simultaneously
- (Sn2)
What is a stepwise process?
- First the LG leaves and then the nucleophile attacks
- Sn1
What is necessary when the substrate is an Alcohol?

Proton transfer at the begging of the Sn1 run
What is Solvolysis?

When the solvent functions as a nucleophile
What doe Protic solvents favor?

Sn1
What doe Polar aprotic solvents favor?

Sn2
What is necessary if the LG is an Alcohol?

A proton transfer at the begging of the Sn2 run
The more substituted alkene is called?
- Zaitsev product
- Generally the major product
The Less substituted alkene is often called the?
- Hofmann product
- Generally the minor product
Which position predominates, Cis or Trans?

Trans
What is Stereoselectivity?

A reaction is stereoselective when a substrate produces two stereoisomers in unequal amounts
How do you predict the which is the major and the minor products?
- 1. Determine the function of the reagent
- 2. Analyze the substrate and determine the expected mechanism
- 3. Consider any relevant regiochemical and stereo chemical requirements
What is a Hofmann product?
- Least substituted
- Least stable alkene
- "Kinetic product
What is a Zaitsev product?
- Most substituted
- Most stable alkene
- Thermodynamic product
What is refioselectivity?

The tendency of a reaction to preferentially produce one constitutional isomer
What is Steroselevctivity?

The tendency of a reaction to produce one of two stereoisomers in unequal amounts
What is Stereospecificity?

Used to describe a reaction in which the configuration of the product is depended on the configuration of the starting material.
What is an example of Stereospecificity?
- R gives one, S gives an other product
- E gives one product and Z gives another
What are examples of a "bulky base"?
- DBN
- DBU
What is the anti-coplanar transition state?
- Staggered conformation
- Lower energy
Syn-coplanar transition state?
- Eclipsed conformation
- Higher energy

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O chem exam 3.txt

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O chem exam 3 test flashcard from lecture only

Updated

2014-10-29T03:14:40Z

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