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• Carbonyl group is C=O. Has higher BP than hydrocarbons and ethers, and lower FP than alcohols.
• Ketones have 3 carbons singly bonded to each other. The middle carbon is the carbonyl carbon. That means the other two carbons on either side are the alpha carbons.
• Special carbon designation: the first adjacent carbon attached to the carbonyl carbon is the alpha carbon; the secondmost adjacent carbon is the beta carbon; the third-most is the gamma carbon; the fourth-most is the delta carbon.
• Naming: find the longest chain containing the carbonyl carbon and ketone; the —e is changed to —one. Number the carbonyl carbon with the lowest possible number.
• If the aldehyde or ketone has the hydroxyl and/or amine group then the hydroxyl substituent gets called hydroxy— and the amine group gets called amino—.

Common Species to Know

Propanone (acetone).

• Carbonyl group is C=O. Has higher BP than hydrocarbons and ethers, and lower FP than alcohols.
• Aldehydes have the carbonyl group.
• R—CHO.
• Polar due to the oxygen (very electronegative).
• Can form hydrogen bonds with water, but cannot form intermolecular h-bonds to “itself” (other molecules of self).
• Can’t h-bond to aldehydes and ketones.
• Lower boiling point than alcohols.
• Has stacking potential.
• Naming saturated aldehydes: determine the longest chain containing the carbonyl; —e changes to —al; carbonyl carbon gets lowest number; number and name the rest of the substituents.
• Naming unsaturated aldehydes: the parent name goes from —ane to —enal; carbonyl carbon gets lowest number; and the rest follows the other unsaturated hydrocarbon rules.
• If the aldehyde or ketone has the hydroxyl and/or amine group then the hydroxyl substituent gets called hydroxy— and the amine group gets called amino—.
• Special carbon designation: the first adjacent carbon attached to the carbonyl carbon is the alpha carbon; the secondmost adjacent carbon is the beta carbon; the third-most is the gamma carbon; the fourth-most is the delta carbon.

Common Species to Know

Formaldehyde (methanal). H—CHO. BP -21 degress C. Disinfectant and tissue fixative/preservative agent.

Ethanal (acetaldehyde).

(Work in progress).

Pre-Lab Questions.

• What is the purpose/function of the saturated NaCl (aq)?
• What is the purpose/function of the anhydrous sodium sulfate?
• What is the purpose/function of the dichloromethane?
• In the separatory funnel, which layer is the aqueous layer and which layer is the organic layer?
• What is the density of water vs. dichloromethane?

Materials and Methods. Clove oil was extracted from ground cloves in three major processes: steam distillation; crude oil extraction; and product purification.

Steam distillation. Ground cloves were boiled in closed, horizontal, simple steam distillation setup (round-bottom boiling flask, Claisen tube, distilling head, water condenser, vacuum adapter, small separatory funnel to renew the water supply, and receiving flask) which yielded 30 mL of distillate.

Crude oil extraction. The distillate was transferred to a separatory funnel. Saturated NaCl solution was added to the distillate to “pull” the aqueous layer out as a diluent for the NaCl (aq). To further separate the aqueous and organic layers, the distillate was washed with a small amount of dichloromethane and then shaken vigorously (venting frequently). Upon settling, the denser organic layer was drained from the separatory funnel into an Erlenmeyer flask. This process was repeated 3 times. This crude extraction was based on the principle: “like dissolves like” or “like is miscible in like”.

Oil purification. Anhydrous Na₂SO₄ was added to the crude oil (repeated if necessary) to absorb any remaining water. When the mixture looked “granular” or turbid, the dried dichloromethane/organic solution was transferred to a pre-weighed boiling flask (boiling chip inside). A rotary evaporator removed the rest of the dichloromethane leaving a purified clove oil product.

Resources:

• https://orgchemboulder.com/Technique/Procedures/Drying/Drying.shtml
• http://employees.oneonta.edu/knauerbr/chem226/226expts/226_expt06_pro.pdf

• Ethers have the structure R1-O-R2. Memory trick: ethers are eithers, R1 or R2 (a play on either/or).
• Are only slightly polar due to the electronegative oxygen (unless there are other functional groups attached).
• Naming. Ethers have the —oxy suffix. The smaller substituent is the “alkoxy” part. The parent chain is the longer chain (used for the base name). For other hydrocarbon groups, change —yl to —oxy. Then, number the position of the alkoxy.
• —OH, hydroxy
• —OCH(3), methoxy (parenthesis are subscripts)
• —OCH(2)CH(3), ethoxy

• R-OH.
• Alcohols are molecules with the alkyl group attached to the —OH hydroxyl group.
• If a hydroxyl group is a substituent in a molecule, it’s called “hydroxy” or “—oxy” instead of “—oxyl”.
• A phenol is a benzene ring with an —OH attached. Phenols are abbreviated as Ar-OH. Ar is for aryl group. Phenols are weak acids and react with strong bases to make salt (alcohols do not salt out, only phenols).
• Due to the O (oxygen is very electronegative) and H, alcohols are polar and can create intermolecular hydrogen bonds.
• Alcohols can have the polar part and they can have the non-polar part. They can be soluble in a polar solvent like water.
• Due to both the London forces and H-bonds, alcohols have higher boiling and melting points.
• Alcohols have a pK(a) similar to water.
• Alcohols have the suffix -ol. In a ring, the OH group gets lowest-numbering (position) priority.
• If there is more than one OH group, use di-, tri-, etc.
• Some special alcohol structures are: 1,2-ethanediol (ethylene glycol); 1,2-propanediol (propylene glycol); 1,2,3-propanetriol (glycerol, glycerin).
• The carbinol carbon is the carbon that the OH group is attached to.
• An alcohol is: primary if the carbinol carbon is bonded to only one other carbon; is secondary if the carbinol carbon is bonded to two other carbons; is tertiary if the carbinol carbon is bonded to 3 other carbons.
• Alcohols can be made: hydration of an alkene; the reduction of an aldehyde or ketone.
• Reactions with alcohols: combustion; dehydration; condensation; oxidation; halogenation.

Methanol

• Wood alcohol.
• Toxic. Can cause blindness.
• Colorless & odorless.
• Fuel in race cars.

Ethanol

• The “alcohol” in beverages.
• Colorless & odorless.
• Product of carbohydrate fermentation.
• Used as solvent, antiseptic, fuel, treatment for alcohol poisoning.

2-Propanol

• Colorless & has a little odor.
• This is rubbing alcohol (typically sold in stores as diluted).
• Toxic to ingest.
• Disinfectant, astringent.

1,2-Ethanediol

• Sweet tasting but toxic.
• Antifreeze.

1,2,3-Propanetriol

• Glycerol.
• Viscous like honey.
• Sweet, non-toxic.
• Additive in foods and beverages.
• One of the products in fat-hydrolysis.
• Water soluble.
• Cosmetics, pharmaceuticals, lubricants, intermediates.

• Aromatics (or Benzene) are a special case of a cyclohexene. This cyclohexene alternates (all the way around) between double and single bonds. The structure has resonance so one configuration (e.g. single-double-single) can spontaneous switch/alternate (e.g. double-single-double) back and forth.
• When the benzene ring is a substituent, it is called a phenyl group (not to be confused with phenol, a benzene ring with a hydroxy substituent making it an alcohol).
• Aromatics do not easily undergo addition reactions, but rather substitution.
• Common reactions include: halogenation, nitration, and sulfonation.

• Alkynes have at least one triple bond in their structure.
• The general formula is C(n)H(2n-2).
• They are unsaturated.
• When naming, specify the positional number of the beginning of the double bond. Try to assign the lowest numbers to the multiple bond. Alkenes get priority over alkynes. If you have to prioritize, the double bond gets priority.
• If there is more than one double bond, use di-, tri-, etc.
• Alkynes end in -yne suffix.
• Naming: double and then triple bonds get priority over alkyl and halogen groups.
• Nonpolar. London forces are additive. When comparing, size comes first then packing efficiency.

• Alkenes have at least one double bond in their structure.
• The general formula is C(n)H(2n).
• They are unsaturated.
• When naming, specify the positional number of the beginning of the double bond. Try to assign the lowest numbers to the double bond. Alkenes get priority over alkynes.
• If there is more than one double bond, use di-, tri-, etc.
• Alkenes end in -ene suffix.
• Naming: double and then triple bonds get priority over alkyl and halogen groups.
• Alkenes and cycloalkanes can have cis- (same side) and trans- (opposite sides) descriptors. Cis- and trans- are specified at the beginning of the name.
• Alkenes may be cyclic.
• Nonpolar. London forces are additive. When comparing, size comes first then packing efficiency.
• The benzene ring (aromatic) is a special case of a cyclical alkene where the cyclohexene alternates between double and single bonds all the way around the ring. This special structure has resonance and the aromatics have a category all of their own.

• Consist of carbons and hydrogens only.
• n-alkanes have the general formula C(n)H(2n+1) where the parenthesis are subscripts.
• Can be straight chain (“n-“) or cyclic (“cyclo” prefix).
• Cycloalkanes have the general formula C(n)H(2n) where the parenthesis are subscripts.
• Find the longest chain. Branches off the longest chain are substituents. Number the chain such that the substituents have the lowest number. Substituents may be described by their position on the parent chain. E.g. 2,3-dimethylpentane. Use di-, tri-, etc. to describe how many substituents there are.
• Nonpolar. London forces are additive. When comparing, size comes first then packing efficiency.
• Consist of single bonds.
• Saturated.
• London forces which are also additive (e.g. the larger the molecule, the greater the london forces). The more “linear” the nature, the more surface area to “stack” the greater the intermolecular london force due to having more surface area to “stick”. In contrast, cycloalkanes have less sticking-surface area.
• Low melting/boiling points (increase with chain length/mass) .
• Usually less dense than water (increase with chain length/mass).
• C1 methane. C2 ethane. C3 propane. C4 butane. After that, the naming follows “normally” pent-, hex-, hept-, oct-, non-, dec-
• Carbons can be classifed as primary, secondary, tertiary, or quatenary depending on if it is bonded to 1 other carbon, 2 other carbons, 3 other carbons, or 4 other carbons respectively.

Cyclic Alkanes

• C(n)H(2n)
• Prefix “cyclo”
• Alkenes and cycloalkanes can have cis- (same side) and trans- (opposite sides) descriptors. Cis- and trans- are specified at the beginning of the name.

Alkyl Group

• Alkyl group is an alkane with one hydrogen removed.
• The alkyl group then acts as a substituent.
• CH3 methyl. CH3CH2- ethyl. CH3CH2CH2- propyl. CH3CH2CH2CH2- butyl. CH3CH2CH2CH2CH2- pentyl. Etc.