New version page

UH CHEM 3332 - Organic Concepts

Type: Lecture Note
Pages: 7

This preview shows page 1-2 out of 7 pages.

View Full Document
View Full Document

End of preview. Want to read all 7 pages?

Upload your study docs or become a GradeBuddy member to access this document.

View Full Document
Unformatted text preview:

CHEM 3332 1st Edition Lecture 2 Outline of Last LectureOverview of Organic I ConceptsI. Lewis Structure/Formal ChargeII. ResonanceIII. Stability of IntermediatesOverview of Reactions and MechanismsI. AdditionsII. EliminationsIII. SubstitutionsIV. RearrangementsCurrent LectureAlkene Oxidations: (addition of oxygen)A. Epoxidation with peroxyacidsAcid – catalyzed ring opening of epoxidesB. HydroxylationC. Oxidative CleavageAddition Mechanisms Continued: Additions of Alkynes A. Additions of H – X: similar to address to alkenes – intermediate is more stable C+ (Mark’s Rule)B. Addition of X2: 3-membered ring intermediate probably too strained; forms more stable C+ addition of first eq. X2 gives cis and trans productsC. Addition of H2: 3 choices 1. Gives alkane with H2 and active catalyst (Pt,Pd,Ni)2. Gives cis-alkene with H2 and Pd/Baso4/quinoline (Lindlar’s catalyst)3. Gives trans-alkene with Na or Li in liquid ammoniaD. Addition of H-OH: Does not give alcohols!1. Mark addition2. Non-Mark additionOxidation of alkynes:1. Mild2. StrongII/III. Elimination/Substitution Reactions:For Pathway A, E+ is δ+ Carbon = substitutionFor Pathway B, E+ is δ+ Hydrogen = emilinationThese notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.SN1/E1: reactivity: 3 > 2 >1 >>> CH3 Step 1:Step 2:SN2:E2:Pathway that has the fastest rxn rate (lowest Ea/lowest E TS) forms major product – anticoplanarOutline of Current Lecture Alkene Oxidations: (addition of oxygen)D. Epoxidation with peroxyacidsAcid – catalyzed ring opening of epoxidesE. HydroxylationF. Oxidative CleavageAddition Mechanisms Continued: Additions of Alkynes E. Additions of H – X: similar to address to alkenes – intermediate is more stable C+ (Mark’s Rule)F. Addition of X2: 3-membered ring intermediate probably too strained; forms more stable C+ addition of first eq. X2 gives cis and trans productsG. Addition of H2: 3 choices 1. Gives alkane with H2 and active catalyst (Pt,Pd,Ni)2. Gives cis-alkene with H2 and Pd/Baso4/quinoline (Lindlar’s catalyst)3. Gives trans-alkene with Na or Li in liquid ammoniaH. Addition of H-OH: Does not give alcohols!1. Mark addition2. Non-Mark additionOxidation of alkynes:3. Mild:4. Strong:II/III. Elimination/Substitution Reactions:For Pathway A, E+ is δ+ Carbon = substitutionFor Pathway B, E+ is δ+ Hydrogen = emilinationSN1/E1: reactivity: 3 > 2 >1 >>> CH3 Step 1:Step 2:SN2:E2:Pathway that has the fastest rxn rate (lowest Ea/lowest E TS) forms major product –


View Full Document
Loading Unlocking...
Login

Join to view Organic Concepts and access 3M+ class-specific study document.

or
We will never post anything without your permission.
Don't have an account?
Sign Up

Join to view Organic Concepts and access 3M+ class-specific study document.

or

By creating an account you agree to our Privacy Policy and Terms Of Use

Already a member?