Free Radical Halogenation

Initiation:      X₂ ----> 2X* (due to heat or light)

Propagation: X* + RH ----> HX + R*

                    R* + X2 ----> RX + X*

Termination: R* + R* ----> R2

    X* + X* ----> X2

    R* + X* ----> RX

Combustion

Dehydration of an alcohol

Alcohol + Acid --> Alkene + (conjugate base + hydronium)

Mechanism: alcohol gains proton from acid, leaves as H₂O, carbocation formed, water abstracts a proton from alcohol molecule, rearrangement may occur

Dehydrohalogenation

Alkyl Halide + Base --> Alkene (+ Halide + protonated base)

strong base --> E2, weak base --> E1

Alkene + H₂ ----> Alkane

Ni, Pd or Pt catalyst; syn addition

Alkene --O₃--> oxidized compound (ketone, aldehyde etc)

called ozonolysis

Example: Alkene + HX ----> Alkane-(HX)

Mechanism: electrophilic attack by alkene on H, carbocation formation, attack of X- on carbocation --> end result is that H and X are added to alkene and the double bond is lost - Markovnikov addition, except in the presence of ROOR

Alkene + H₂O ----> Alcohol

Alkene + HgOAC + reducing agent --> Alcohol

Anti addition of alcohol

Alkene + BH₃ ----> Alcohol

Anti-Markovnikiv and syn addition

Alkene + X₂ ----> Dihaloalkene

halohydrin formed when the reaction takes place with water

Alcohol + alkene ----> product

product = alcohol added to alkene without the H and double bond

Primary Alcohol + oxidizing agent ----> Aldehyde ----> carboxylic acid

Secondary Alcohol + oxidizing agent ----> Ketone

Alcohol + HX ----> alkyl halide 

Mechanism -- SN1 (carbocation formation), acid catalyzed

OR 

Alcohol + PBr₃/AlCl₃ -------> Alkyl halide

no acid catalysis necessary

Pinacol Rearrangement

Vic Diol + Hot Sulfuric Acid ----> Ketone

Mechanism - One hydroxyl is protonated and leaves, carbocation formed, a methyl group rearranges to the carbocation converting the tertiary carbon bearing atom to secondary, OH is reduced to carbonyl (=O)

Aldehyde + Alcohol ----> Hemiacetal + Alcohol ----> Acetal

Structure of hemiacetal - C bonded to R, OR, H, OH

Structure of acetal - C bonded to R, OR, H, OR

Ketone + Alcohol ----> Hemiketal + Alcohol ----> Ketal

Hemiketal --> C bonded to: R, R, OR, OH

Ketal --> C bonded to R, R, OR, OR

Aldehyde + aldehyde OR

Aldehyde + Ketone OR

Ketone + Ketone

Base abstracts alpha proton --> enolate ion --> O acts as nucleophile and attacked the second molecule's carbonyl --> alkoxide --> aldol --> can be dehydrated to an enal

R-CO-CH₃ (ketone) + Cl₂   ------->   R-CO-CCl₃

R-CO-CCl₃ + OH^-   -------> R-CO-OH + CCl₃^-

----------------> R-CO-O^- + CHCl₃

Ylide + Ketone ----> Betaine ----> Alkene

Ylide - Ph₃P-C(HR)^-

Betaine - formed when the ylide adds to the ketone forming a compound with Ph3P⁺ and O^-

Alkene formed when O^- attacked the P⁺ and separate from the molecule as Ph₃P=O

Carboxylic Acid + SOCl₂/PCl₃/PCl₅ ----> Acyl chloride

acyl group consists of R-C=O

Acyl Chloride + 

H₂O ----------> RCOOH - carboxylic acid

ROH ----------> RCOOR - ester

RNH₂ ---------> RCONHR - amide

RCOOH -------> RCOOCOR - anhydride

Reverse is true when these derivatives are hydrolyzed with water

Carboxylic Acid + Alcohol ----> Ester

hydroxyl replaced by alkoxy

Ester + Alcohol ----> Transester

one alkoxy group is substituted for the other

Acetoacetic Ester ---Base/Alkyl Halide---> Alkylacetoacetic ester ---acid/heat---> Ketone + CO₂

Acetoacetic ester - CH₃CO-CH₂-COOC₂H₅

Amine + Ketone ----> Enamine/Imine

N: attacks carbonyl and adds. Primary amine will make imine (N's lost H for double bond; N involved in double bond), secondary amine will make enamine (the alpha H is lost; N not involved in double bond)

Imine and Enamine are Tautomers

Ketone/Aldehyde + Hydrazine ----heat+base----> Alkane!

O replaced by 2 H's

Amine + R-X -----> Alkylated Amine + HX

*can even form a quarternary amine:

NR₃ + R-X ---> NR₄⁺ + X^-

Quaternary Aminonium Hydroxide --Heat--> Alkene

Quaternary Aminonium Hydroxide: NR₄⁺OH^-

HNO2-->protonation--> NO+ ion

NRH2 + NO ---->N(NO)(R)(H2)+(N-nitrosoammonium)

N-nitrosoammonium---->:N(NO)(R)(H)----> RN=N-OH (tautomerization)

---> R-N=-N+ (diazonium ion)

diazonium ion can be replaced by OH, X, H, N=N-Ar

Tosylate: Ch3-Benzene-SO3-R

ROH + Ch3-Benzene-SO2Cl -----> Ch3-Benzene-SO2-OR + HCl

Mesylate is similar: Ch3-SO2-OR

Tosylates and mesylates retain stereochemistry