Chapter 11 Flashcards
Oxidation:
______: C-O, C-N, or C-X bonds
______: C-H bonds
form
break
Reduction:
______: C-O, C-N, or C-X bonds
______: C-H bonds
break
form
_______ results in less bonds to O and more bonds to H
reduction
_______ results in more bonds to O and less bonds to H
oxidation
What oxidation agents can change an alcohol into a carboxylic acid?
Na2Cr2O7
H2SO4
H2O
or NaOCl, pyridineish ring in excess
What happens when you try to oxidize a 3° ROH
inert to oxidation
NO REACTION!
NaOCl, pyridinish ring only works for ___ ROH’s
1°
NaOCl, HOAc only works for ___ ROH’s
2°
Alcohols are very versatile and can act as _______ and _______
nucleophiles
electrophiles
What bond is broken when alcohols react as nucleophiles?
O- -H bond
What bond is broken when alcohols react as electrophiles?
C- -O bond
HCl, ZnCl2 are the _______ reagents
Lucas
explain the lucas test and how it reacts with 1°, 2°, 3° alcohols at predictable rates
1°: cloudy in more than 6 mins
2°: cloudy in 1-5 minutes
3°: cloudy in less than 1 min
the limitations of hydrohalic acids with alcohols is:
1) poor _______ of alkyl chlorides from primary or secondary alcohols
2) _______ competes with substitution
3) carbocation intermediate may undergo _______
4) limited ability to make alkyl _______ form __
1) yield
2) elimination
3) rearrangement
4) iodides from HI
What are the 3 reactions to turn ROH into a better leaving group?
1) Strong acid (HCl or HBr)
2) OTs or OMs
3) turn it into X (special reagents)
What are the three special reagents for turning OH into X
1) SOCl2
2) PBr3
3) PI3
When using SOCl2, what happens to the stereochemistry of the product?
retention
When using PBr3 or PI3, what happens to the stereochemistry of the product?
inversion
What is the driving force of SOCl2 reaction?
SO2 (g) leaving
Reduction of alcohols must be accomplished in ___ steps
- very rare
2
What are the two ways alcohols can be reduced?
1) E1 (H2SO4) then H2, Pt
2) TsCl, pyridine then LiAlH4
2 steps
How does a pinacol rearrangement start? and what is the driving force?
Oxygen grabbing a H of H2SO4
Octet rule is the driving force
Glycols can be oxidative cleaved by periodic acid (HIO4) to form the corresponding _______ and _______
aldehyde and ketone
_______ + _______ + _______ always results in FISCHER esterfication
carboxylic acid + ROH + Acid
What is the driving force of Fischer Esterification?
Removal of water
_______ + _______ + _______ always results in regular esterfication
acid chloride + ROH + base
- base usually pyridine
What is preferred, Fischer esterification or esterification
Esterification
What are the three esters of inorganic acid?
1) Sulfate ester
2) Nitrate ester
3) Phosphate ester
sulfate ions are good ____: Nuc reacts with sulfate esters to give alkylated products
LG
The best-known nitrate ester is “nitroglycerin” = _______
Explosive (Dynomite)
Phosphate ester linkages compose the backbone of nucleic acids ______ and ______! they carry the genetic information of the cell
RNA and DNA
