OXYGEN-CONTAINING FUNCTIONAL GROUP Flashcards
- member of Group VIA of the periodic table and thus possess six valence electrons.
- To complete its octet by electron sharing, it can form either two single bonds or a double bond.
OXYGEN
- Generalized formula: _____________
- Is an organic compound in which an – OH group is bonded to a saturated carbon atom
- Alcohols in which the hydroxyl group is attached to a ring of carbon atoms (a cycloalkyl group) rather than a chain of carbon atoms (an alkyl group) also exist.
- ROH
alcohols that possess more than one hydroxyl group
o two hydroxyl groups is named as _____
o three hydroxyl groups is named as _____
o the final -e of the parent alkane name is retained for pronunciation reasons
- These two alcohols are synthesized, respectively, from the alkenes ethylene and propylene: __________ & ___________
polyhydroxy alcohols
- diol
- triol
- ethylene glycol and propylene glycol
Classification of Alcohols
A. Based on the number of R group/s bonded to the carbon bearing the -OH group
B. Based on the number of -OH groups
A.
1. Primary Alcohol
2. Secondary Alcohol
3. Tertiary Alcohol
B.
1. Monohydric
2. Dihydric
3. Trihydric
4. Polyhydric
- Alcohol molecules have both _______ and _______ character
- The physical properties of an alcohol depend on whether the polar or the nonpolar portion of its structure “dominates.” Factors that determine this include the length of the nonpolar carbon chain present and the number of polar hydroxyl groups present.
- polar and nonpolar
o For __________, unbranched-chain alcohols with an – OH group on an end carbon, increases as the length of the carbon chain increases.
(Results from increasing London forces with increasing carbon-chain length.)
o Alcohols with more than one hydroxyl group present have significantly ________ boiling points than their monohydroxy counterparts.
- 1-alcohols
- higher
_____________ alcohols are soluble in water in all proportions
o As carbon-chain length increases beyond ___, solubility in water rapidly ________ because of the ___________ nonpolar character of the alcohol.
o Alcohols with ___________ are more soluble in water than their counterparts with only one —OH group.
- Increased hydrogen bonding is responsible for this.
- Diols containing as many as seven carbon atoms show appreciable solubility in water.
- Small monohydroxy
- 3C; decreases; increasingly
- two —OH groups present
Chemical Reactions of Alcohols
A. Combustion
B. Dehydration
C. Condensation
D. Oxidation
E. Halogenation
- alcohols are also flammable; as with hydrocarbons, the combustion products are carbon
dioxide and water. - used as automotive fuels.
- methanol
- ethanol
- alcohol-gasoline mixtures
COMBUSTION
- oxygen is needed
- A chemical reaction in which water is formed from the removal of the components of water (H and OH) from a single reactant.
- this is an example of an ___________
- Two groups or two atoms on neighboring carbon atoms are removed, or eliminated, from a molecule, leaving a multiple bond between the carbon atoms.
- elimination reaction
DEHYDRATION
H2SO4 (180)
- 1: alkene
- 2: alkene
- 3*: alkene
- A chemical reaction in which two molecules combine to form a larger one and a molecule of water.
- Commonly occur in living organisms
CONDENSATION
- H2SO4 (140*)
- 1*: ether
- _________ and _________, the two types of oxidizable alcohols, yield different products upon oxidation.
- A ________ produces an aldehyde that is often then further oxidized to a __________
- and a 2° alcohol produces a _______
- Primary and secondary alcohols
- 1° alcohol; carboxylic acid
- ketone
OXIDATION
- KMnO4 or K2Cr2O7
- 1*: aldehyde - carboxylic acid
- 2*: ketone
- 3*: no reaction
- 4*: no reaction
- A ________ is substituted for the hydroxyl group, producing an __________.
- A single product is produced in which the halogen atom is found only where the -OH group was originally located.
- Several different halogen-containing reactants, including ___________ PX3; X is Cl or Br), are useful in producing alkyl halides from alcohols.
- heating of the reactants is REQUIRED
- halogen; alkyl halide
- phosphorus trihalides
HALOGENATION
- alcohol - alkyl halide
PREPARATION OF ALCOHOLS
Alkene Hydration
- H2SO4
- H2O
alkene - alcohol
- _______: a compound that contains and -OH group bonded to a benzene ring
- General Formula: Ar-OH, where Ar represents an aryl group.
- Phenol