E3P1 Flashcards
(30 cards)
what are ethers?
oxygen linked to 2 carbon atoms
R-O-R
symmetrical vs unsymmetrical ethers are?
-ethers with the same R groups
-ethers with different R groups
if molecular weight of an ether is small, what is the boiling point?
-boiling point will be small as well
boiling point of an ether correlates
with its molecular weight
the bigger the molecular weight, the higher the boiling point
cyclic ethers are?
one or more oxygen atoms contained within a ring
propylene oxide
triangle between two C and O with methyl group on right C
dioxane
cyclohexane with two O top and bottom
furan
upside down pentane with double bonds on opposite sides and O at tip
tertrahydrofuran
like furan without double bonds
nomenclature for ethers containing other functional groups
-they act as? aka
-if more than 2 carbons?
-where and how to name alkoxy group?
-acts as a substituted —> alkoxy group
-if more than 2 carbons, number where the O is coming off
-first start off with suffix of “meth-“ or “eth-“ depending on how many carbons are attached to the O. then put this in the front of the name
ex: 2-methoxypentane
alkoxy group
-substituent O on larger hydrocarbon group
methoxy
CH3-O-R
ethoxy
CH3CH2-O-R
common names for ethers(don’t contain any functional groups)
-formed by?
-listed in?
-if two groups are the same?
-by naming two hydrocarbon groups attached to the oxygen atom and adding “ether” as parent name
-listed in alphabetical order
-if two groups are same, add “di-“
ex: ethyl phenyl ether
the alcohol functional group has priority over? except?
over ethers and any functional group EXCEPT carboxylic acids, ketones and aldehydes
aromatic ethers
oxygen bonded to an aromatic ring and/or an alkyl or aryl group
ex: o-methoxyphenol
Williamson ether synthesis
-alcohols react to?
1.
2.
3
-yield ethers
1. R’OH + HBr —-> RBr + HOH
2. HOR + NaH —-> Na+O^-R + H2
3. R’X + Na+O^-R —-> R’OR + NaBr
synthesis alcohols
just break it apart starting from the left of O and the right of O
preparation of symmetrical ethers
-limitation:
-limitation: only 1• ROH
- 2ROH
H2SO4
———>
140C
ROR + H2O
properties of ethers
-polar or no polar? because?
-b.p compared to alcohol?
-b.p compared to alkanes?
-solubility?
-flammable?
-reactive? makes a good?
-forms?
-polar but no hydrogen bonding
-lower boiling point than alcohols of similar m.m
-higher b.p than alkanes of similar m.m
-slight solubility for low m.m ethers in water
-flammable
-not very reactive. makes a good solvent
-forms peroxide (-O-O-) in presence of light or radical initiators (unwanted reaction)
crown ethers
-format?
-X & Y mean?
-are able to?
-bigger crown means?
- X-Crown-Y
-X= total atoms in ring
-Y= total oxygens
-able to solvate metal cations
-bigger crowns can capture bigger cations due to the oxygens polarity and negativity
thiols
-format?
-analogs of?
R-SH
-analogs of alcohol (R-OH)
sulfides
-format?
-analogs of?
R-S-R
-analogs of ethers (R-O-R)
nomenclature of thiols
-similar way as?
-keep ?
-suffix?
-similar way as alcohols
-keep the “e”
-thiol
ex: ethanethiol
