hydrocarbon derivatives:
DESCRIPTION
Halocarbons, Alcohols, & Ethers. Hydrocarbon Derivatives:. Hydrocarbons. Contain only carbon & hydrogen carbon can also form strong covalent bonds with other elements such as: O, N, F, Cl, Br, I, S, & P. Functional Group. - PowerPoint PPT PresentationTRANSCRIPT
Hydrocarbon Derivatives:
Halocarbons, Alcohols, & Ethers
Hydrocarbons
• Contain only carbon & hydrogen
• carbon can also form strong covalent bonds with other elements such as:
O, N, F, Cl, Br, I, S, & P
Functional Group
• functional group: atom or group atoms in organic molecule that always behaves the same way
• Adding functional group changes chemical & physical properties in specific ways– depends on type functional group added
Intermolecular Forces• Determine Boiling Point & Solubility• Van der Waals or dispersion: weakest
– nonpolar molecules• Dipole-dipole: intermediate strength
– molecule has atoms with different electronegativities
– atomsatoms not not arranged symmetrically• Hydrogen bonding: strongest
– molecules contain H bonded to F, O, or N
Functional Groups1.Halocarbons2.Alcohols3.Ether4.Aldehydes5.Ketones6.Carboxylic Acid7.Ester8.Amines9.Amide10.Amino Acid
Organic Halides
• One (or more) hydrogen atoms in alkane is replaced with halogen atom
(F, Cl, Br, or I)
• No longerNo longer hydrocarbons! • called halocarbons, alkyl halides or organic halides
Naming Halides
• Figure out backbone name• prefixes specify substituent: fluoro, chloro, bromo, iodo• use di, tri, tetra (if more than one same thing)• Give location(s) of halogen(s)
– tell # C attached to in backbone
CH3Cl CH3CHFCH3
H H–C–Cl H
chloromethane
H H HH–C–C–C–H H F H
2-fluoropropane
C3H7F
Naming Halides
CH3CCl2CHClCH3
H Cl Cl H H
H – C C – – C C – – C C – – CC – H H Cl ClCl Cl H
2,2,3-trichlorotrichlorobutanebutane
C4H7Cl3
Ranking Halogens
• If more than 1 kind halogen atom present – name them alphabetically
• # C’s so lowest number goes to halogen alphabetically first
Different Halogens
Chlorine is 1st alphabetically, so it determines numbering:
4 3 2 1
2-chloro-4-fluoro-3-iodobutane
BrCH3CH2CHCHCH3
I
Name:
3-bromo 2-iodo pentane
F ClHCCH F Cl
1,1-dichloro-2,2-difluoroethane
Properties of Halocarbons• alkane & alkyl halide of similar size & shape:
– alkyl halide has higher bp & higher density Why?
• CH4: bp = -162C
density = 0.423 g/ml
• CH3Cl: bp = -24C
density = 0.911 g/ml
Stronger intermolecular forcesStronger intermolecular forces
1.516155CH3CH2CH2CH2CH2I1-iodopentane
1.218130CH3CH2CH2CH2CH2Br1-bromopentane
0.882108CH3CH2CH2CH2CH2Cl1-chloropentane
0.79163CH3CH2CH2CH2CH2F1-fluoropentane
0.62636CH3CH2CH2CH2CH3
pentane
Density(g/ml)
Boiling Point(C)
Inc Inc
Uses of Alkyl Halides
• Cleaners & solvents
• Examples: – Teflon & PVC’s – Refrigerants (used to be chlorofluorocarbons- now
hydrofluorocarbons)
Halogen Derivatives• CH3Cl = local anesthetic
• CHCl3 = solvent, general anesthetic
• CHI3 = antiseptic
• CCl4 = dry cleaning solvent
• CF2Cl2 = refrigerant
• Fluorocarbons = teflon, lubricants, synthetic blood
• Chlorofluorocarbons = aerosol propellants,
refrigerants
Table R
• General Formula halocarbons: R-X
– R represents entire hydrocarbon part of molecule
– X represents halogen (F, Cl, Br, or I)
Alcohols
• OH group replaces H in hydrocarbon• OH group called: hydroxyl group
HHCH H
OHOH HHCOHOH H
Alcohols are nonnonelectrolytes!
• hydroxyl group = hydroxide ion of inorganic bases - does not form ions in water!
• hydroxyl group is polar – alcohols soluble in water
Naming AlcohOLOLs
• Based on alkane name• Name parent chain
– Drop the –e and add –olol
• If parent chain has 3+ C’s, # which C OH group(s) attached to
Naming
H H H HHCCCCH OH H H H
1-Butanolbp = 100C
H H H HHCCCCH H OH H H
2-ButanolBp = 115C
Note: Never more than one OH group per C
More than 1 hydroxyl group
• Prefixes di-, tri-, tetra- used before ol ending tell # of hydroxyl groups
Classifying Alcohols
• By # of hydroxyl groups–Monohydroxy: 1 hydroxyl group–Dihydroxy: 2 OH groups–Trihydroxy: 3 OH groups
• By position of each hydroxyl group on main carbon chain
Monohydroxy Alcohols
• PrimaryPrimary: hydroxyl group attached to end C of chain or branch
• SecondarySecondary: hydroxyl group attached to C in chain bonded to 2 other C’s
• TertiaryTertiary: hydroxyl group attached to C at a branch point (C bonded to 3 other C’s)
H H H HH-C-C-C-C-O-H H H H H
1-butanol(primary)
H H H HH-C-C-C-C-H H H O H H
2-butanol(secondary)
H H-C-H H HH-C-C-C-H H O H H
2-methyl 2-propanol(Tertiary)22
H HH-C─C-H O O H H
H H HH-C─C─C-H O O O H H H
Dihydroxy Trihydroxy
Properties of Alcohols
• Contain: H bonded to O atom– Hydrogen Bonding Hydrogen Bonding
• Alcohols have higher bphigher bp than corresponding alkane
• ‘‘Like dissolves Like’Like dissolves Like’ – Alcohols tend to be very soluble in water
OR
H
OR
H-
++
+
-
H-bond
Which compound has the highest boiling point?
A. CH4
B. C2H6
C. C3H8
D. C3H7OH
Correct response = D
Table R
• General Formula Alcohols: ROH• R represents entire hydrocarbon part of
molecule• OH is hydroxyl group
Ethers
• General formula ROR – where R may or may not be same as R
• R and R are hydrocarbon branches• O is oxygen bridge• Ethers are not linear
– they are bent, like water
Properties of Ethers
• PurePure ether: no hydrogen bonding – weak dipole-dipole interactions – bent, like H2O
• Ethyl ether once used as anesthesia
Properties of Ethers
• Compared to alkanes (same # C’s):– Higher bp’s than similar alkanes– More soluble in water than alkanes
• Compared to alcohols (same # C’s):– Lower bp’s than similar alcohols– Much less soluble in water than alcohols
Naming Ethers
• If both hydrocarbon branches are identical:– name the branch (once) & add the word ether
• If 2 branches are different: – list them in alphabetical order followed by the
word ether
H HHCOCH H H
Methyl Ether
H H H H H HHCCCOCCCH H H H H H H
Propyl Ether
H H H HHCOCCCH H H H H
Methylpropyl Ether