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What do these prefixes describe?

Vinyl

Allyl

Methylene

Vinyl= monosubstituted ethylenes (vinyl chloride= CH2=CHCl)

 

Allyl= C3 substituted propylene (allyl bromide=

CH2=CHCH2Br)

 

Methylene= -CH2 group (methylene cyclohexane= a cyclohexane with a CH2 group…double bond from cyclic C to a CH2)

 

      Name these common substituents
1.   CH3          2. CH3         3.  CH3
      |                |                |
H3C-C-       H3C-C-CH2–      HC-    
      |                |                |
      CH3              CH3              CH3
 
      4.    CH3                 5.      CH3
             |                          | 
CH3-CH2-CH-                CH3-CH-CH2

1. t-butyl (tert-butyl)
2. neopentyl
3. isopropyl
4. sec-butyl
5. isobutyl

Common names for ethene and ethyne.

 

When naming a molecule with both a double and triple bond in it, which gets the lower carbon number?

Ethene= ethylene

Ethyne= acetylene

 

When both in the same molecule, the double bond gets the lower number

CH3CH=CH-C=C-CH3

2-hexen-4-yne

What is a vicinal?

What is a geminal?

 

Why are geminals/hydrates not often seen?

Vicinals= diols with hydroxyl groups on adjacent carbons

Geminal aka hydrates= diols with hydroxyl groups on the same carbon

 

Geminals/hydrates not often seen because they spontaneously lose water and produce carbonyls.

What is an ether?

 

What is a 3-membered cyclic ether called?

 

Common names for:

methanal

ethanal

propanal

Ether=   R-O-R

 

3-membered cyclic ethers= oxiranes or epoxides – or ethylene oxide

 

Methanal= Formaldehyde

Ethanal= Acetaldehyde

Propanal= Propionaldehyde

Common names for:

2-propanone

methanoic acid

ethanoic acid

propanoic acid

2-propanone= acetone

methanoic acid= formic acid

ethanoic acid= acetic acid

propanoic acid= propionic acid

Prefix and suffix for:

esters

acyl halides

 amides

nitriles/cyanide

 thiols

imines

ethers

…and just prefixes for:

sulfides

nitros

azides

diazos

                        Prefix:                 Suffix:
Esters           alkoxycarbonyl-       -oate
Acyl halides     halocarbonyl-      –oyl halide
Amides               amido-                 -amide
Nitriles/Cyanide   cyano-                  nitrile
Thiols (RSH)     sulfhydryl-                -thiol 
Imines (R2C=NR’); imino- ; ; ; ; ; ; ; -imine
Ethers ; ; ; ; ;;;;;; alkoxy-;;;;;;;;;;;;;;;;; -ether
Sulfide (R2S) ; ;; alkothio- ; ; ;
Nitros (RNO2) ; ;;;; nitro-
Azides (RN3) ; ; ;;; azido-
Diazo (RN2+) ; ; ;;; diazo-
; ; ;

What are structural/confirmational isomers?

;

What are enantiomers?

;

;

Structure/confirmational isomers only share a molecular formula.

;

Enantiomers are chiral objects that are nonsuperimposable mirror images.

Put the following bases in order from strongest to weakest: RCO2, ROH, HO, RO, H2O

;

Put the following nucleophiles in order from strongest to weakest when in a protic solvent: CN, HO, Br, I, F, H2O, Cl, RO

;

Put the following nucleophiles in order from strongest to weakest in when in an aprotic solvent: Cl, Br, F, I

;

Put the following leaving groups in order of best to worst:

Cl, Br, F, I

Base Strength:

RO;OH;RCO2;ROH;H2O

;

Nucleophile strength in a protic solvent (larger atoms=stronger Nu in protic solvents:

CN;I;RO;HO;Br;Cl;F;H2O

;

Nucleophile strength in an aprotic solvent (strong bases=stronger; Nu in aprotic solvents):

;F;Cl;Br;I

;

Leaving group strength (weak base=better LG):

I;Br;Cl;F

;

Are SN1 and SN2 reactions favored in protic or aprotic solvents?

;

What happens to the stereochemistry of SN1 and SN2 reactions?

SN1 reactions are favored in polar protic solvents.

SN2 reactions are favored in polar aprotic solvents.

;

If the reactant is optically active, SN1 reactions produce racemic mixtures.

If the reactant is optically active, SN2 reactions produce a product with an inversion of stereochemistry (still optically active).

As you increase branching, what happens to the boiling point and density?

As molecular weight increases, what happens to the melting and boiling points and density?

More branching means decreased boiling point and decreased density (decrease the surface area so decrease intermolecular forces).

As molecular weight increases, melting and boiling points also increase and density increases.

Addition of cold, dilute KMnO4 to an alkene yields…

;

Addition of hot, basic KMnO4 to a non-terminal alkene…

Addn of cold, dilute KMnO4 to an alkene yields a 1,2 diol (vicinal diol/glycol), syn orientation.

;

Addn of hot, basic KMnO4 cleaves the non-terminal alkene to produce a carboxylic acid and carbon dioxide…if the double bonded carbon is disubstituted, it produces a ketone.

Steps for the addition of HX to an alkene.

;

Steps for the addition of X2 to an alkene.

Addition of HX to an alkene:

step 1: Addn of H+ to less highly substituted C to form a stable C+ (Markovnikov’s)

step 2: Addn of halide to the positive C

 

Addition of X2 to an alkene:

step 1: double bond displaces X and forms a cyclic halonium ion

step 2: X attacks to form a dihalide compound in anti addition.

Steps for addition of H2O to an alkene.

 

Steps for addition of a free radical (such as Br) to an alkene/alkyne.

Addition of H2O to an alkene:
step 1: potonation of the double bond (Markovnikov’s) to form a stable C+
step 2: addn of H2O to positively charged C
step 3: loss of H+ to form an alcohol;
;
Addition of a free radical to an alkene:
step 1: addn of the free radical to the less substituted C (anti-Markovnikov b/c adds H second)
step 2: addn of H to the free radical C

Steps of hydroboration and what it produces.

;

Products of ozonolysis with Zn/H2O.

;

Products of ozonolysis with NaBH4/CH3OH.

Hydroboration:
step 1: B attaches to the less sterically hindered C (anti-Markovnikov b/c H adds second)
step 2: oxidation-hydrolysis with peroxide and an aqueous base (replacement of BH3 with OH)
…produces an alcohol in an anti-Markovnikov fasion with syn addition (of H and OH).
;
Ozonolysis with Zn/H2O cleaves the double bond to form carbonyls (aldehydes or ketones…not carboxylic acids).
;
Ozonolysis with NaBH4/CH3OH produces alcohols.

What do peroxycarboxylic acids (such as CH3CO3H and mcpba) do to alkenes? What is the product?

;

Polymerization occurs under…

;

How does the boiling point compare between internal alkenes/alkynes and terminal alkenes/alkynes?

Peroxycarboxylic acids oxidize alkenes and produce oxiranes.

;

Polymerization occurs under high temperatures and high pressures.

;

Internal alkenes/alkynes boil at higher temps than terminal alkenes/alkynes.

Elimination of 2HX’s from a vicinal dihalide to form an alkyne requires…
Elimination of 2HX’s for a vicinal dihalide to form an alkyne requires high temps and a strong base.
Difference between constitutional and conformational isomers.

Constitutional isomers= different atom connectivity

Conformational isomers= different 3D arrangement

What are the structures of the following amine compounds:

Amide

;Carbamate/Urethane

Isocyanate

Enamine

Imine

Nitrile/Cyanide

Nitro

Diazo

Azide

Amide:; O;;;;;; (carboxyl + amine)

; ; ; ; ;;; ||

;;;;;;;;; RCNR2 ; ; ;;

Carbamate/Urethane: ; O;;;;; (Ester + amine)

; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ;;; ||

; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ROCNR2

Isocyanate: ;; R=O=C=NR; (add alcohol-;carbamate)

Enamine: ; R2=CRNR2 (amine equivalent of anenol)

Imine:; R2C=NR; (carbon=nitrogen)

Nitrile/Cyanide:; C=N; (C triple bonded to N)

Nitro: -NO2

Diazo: R2C=N=N; (N2 group)

Azide: R-N=N=N; (N3 group)

;

;

;

alkyl halide + ammonia -;….+base-;

(CH3Br + NH3 -;_____+NaOH-;_____)

Alkyl halide + ammonia -; alkylammonium halide salt

alkylammonium halide salt + base -; alkyl amine

CH3Br+NH3-; CH3NH3+Br+NaOH-; CH3NH2 + NaBr +H2O

What is Markovnikov’s Rule?

 

What conditions often cause free radical addition?

Markovnikov’s= When adding a protic acid HX to a double bond, the H will add to the less substituted carbon, and the X will add to the more substituted carbon after.

;

Peroxides, oxygen, and UV light cause free radical addition (which is anti-markovnikov…free radical adds before the free H).

How can you form an amine from a nitro compound?

;

How can you form an amine from a nitrile?

;

How can you form an amine from an imine?

Nitro compound + reducing agent such as Zn or Fe in dilute HCl turns the nitro group into a primary amine.

;

Nitrile compound + hydrogen and a catalyst or LAH creates a primary amine

CH3CH2C=N + LAH -; CH3CH2CH2NH2

;

Aldehyde or ketone + ammonia -; Imine

Imine + hydrogen and a catalyst -; amine

; O;;;;;;;;;;;;;;;;;;;;; NH;;;;;;;;;;;;;;;;;;;;;;;;;;;;; NH2

; ||;; +; NH3 -; ||;; + H2-Ni/RaneyNi -;; |

RCR ;;;;;;;;;;;;; RCR;;;;;;;;;;;;;;;;;;;;;;;;;;;; RCR

What is Zaitsev’s Rule?

 

 

Zaitsev’s rule states that if an elimination reaction can produce two products, the more highly substituted double bond will be the major product.

Describe the frequencies these bonds would absorb in an IR spectrum:

Carbonyl; (C=O)

Alcohol or Acid (O-H)

Amine (N-H)

Carbonyl (C=O) ~1750

;Alcohol or Acid (O-H) ~3000 (broad)

Amine (N-H) ~3000 (sharp)

How can you form an amine from an amide?

Amide + LAH -; amine

; O

; ||;;;; +; LAH -;

RCNH2;;;;;;;;;;;;;; RCNH2

x

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