Chapter 4

Covalent bonds can be either polar or non polar Polar – covalent bonds with equal sharing of e-’s Non-Polar – covalent bonds with unequal sharing of e-’s

Always form nonpolar molecules Equal distribution of electrons No charged areas

In symmetrical molecules  nonpolar molecules Bonds are equidistant from each other if symmetric In unsymmetrical molecules  polar molecules Charged areas due to uneven e- distribution

σ+σ- H – Cl

 Nonpolar molecules are held together by LDF (attractions between temporary dipoles and induced dipoles) Induced dipoles – temporary dipoles formed by the attraction of one atoms nucleus for another atom’s e-’s

Dipole-Dipole attractions Attraction between oppositely charged poles on 2 polar molecules Hydrogen Bonds (very strong dipole-dipole) The attraction between the + charges H on one dipole and the – charged highly e-neg element in the polar molecule.

Order of strength… H-Bond>dipole-dipole>LDF

Both alcohols and phenol contain OH OH – Hydroxyl group Alcohol  General Formula = R-OH Phenol  General Formula = Ar-OH

The difference between alcohols and phenol is the O added to make the OH group Results in 3 differences…

1. Alkanes = nonpolar molecules with LDF Alcohols = have polar areas and H Bonding C – C – C – O H σ- σ+ Nonpolar Region

2. Alkanes cannot dissolve in H 2 O while shorter (2-5 C’s) alcohols can 3. Alcohols have higher boiling points that their corresponding alkanes

C = -162 °CC-OH = 64.5 °C C-C = °CC-C-OH = 78.3 °C C-C-C = 0 °CC-C-C-OH = 118 °C

1° alcohol – hydroxyl group on 1° C C-C-C-OH 2° alcohol – hydroxyl group on 2° C C-C-C OH 3° alcohol – hydroxyl group on 3° C C C-C-C OH

1.Drop –e from the alkane & add –ol 2.# from end closest to –OH & add the # in front of the “main”chain 3.The –OH has priority over other functional groups covered

C-C-C-OH C-C-C-C-C-C-OH OH C-C-C-C-C-C-C OH OH OH OH OH C-C-C-CC-C-C-C-C

Cl OH C OH C-C-C-CC-C-C-C-C-C Br Br Br OH C-C-C-C-C-C-C-C-C OH OH C-C-C-C-CC-C-C-C-C

OH OH C-C-C-C-C-C-C OH OH OH Cl OH Cl C-C-C-C-C-CC-C-C-C-C-C-C C-C

1.1°Alcohols a.) Alkyl halide + water  alcohol + hydrogen halide RX + H 2 O  R-OH + HX Form 1-Propanol (str & cond) Cl OH C-C-C + H 2 O  C-C-C + HCl CH 3 CH 2 CH 2 Cl + H 2 O  CH 3 CH 2 CH 2 OH + HCl

React ethylfluoride with water (str,cond, name product)

b.) Alkyl + metal  alcohol + metal halide hydroxide halide RX + M + OH -  ROH + MX (M Can be Li +,Na +,or K + )

Form Heptanol (str and Cond) (you can choose any of the 3 metals – Na is most common) C-C-C-C-C-C-C-Cl + NaOH  C-C-C-C-C-C-C-OH + NaCl CH 3 (CH 2 ) 5 CH 2 Cl + NaOH  CH 3 (CH 2 ) 5 CH 2 OH + NaCl

React methyl bromide with potassium hydroxide

Synthesize – to form an organic compound from the pure hydrocarbon (usually needs more than one step) Synthesis of a 1° Alcohol requires 2 steps 1.RH + Cl 2  RCl + HCl 2.RCl + H 2 O (or NaOH)  ROH + HCl Na could be Li or K (or NaCl)

Synthesize methanol (str) 1.C + Cl 2  CCl + HCl 2.CCl + NaOH (or H 2 O)  COH + NaCl (or HCl)

Synthesize 1-Pentanol (condensed) CH 3 (CH 2 ) 3 CH 3 + Cl 2  CH 3 (CH 2 ) 3 CH 2 Cl + HCl CH 3 (CH 2 ) 3 CH 2 Cl + KOH (or H 2 O)  CH 3 (CH 2 ) 3 CH 2 OH + KCl (or HCl)

1.Alkene + water  2° or 3° Alcohol Hydrate 3-ethyl-2-pentene (str,cond,name prdct)

2. RX + H 2 O  ROH + HX React 3-iodoheptane with water (str, cond, name product)

3. RX + M + OH -  ROH + MX React 2-fluoropropane with Lithium Hydroxide (str, cond, name product)

Form 2-hexanol 3 ways (str) Form 3-octanol 3 ways (cond) Synthesize 2 - Butanol

1.Halogenation (same as alkanes) R-OH + X 2  R-XOH + HX Form 3-bromo-1-heptanol (3- bromoheptanol) (str and cond) Br C-C-C-C-C-C-C-OH +Br 2  C-C-C-C-C-C-C-OH

Form 1,2,2,3-tetrafluorohexanol (*1-hexanol) (str&cond) Form 3-iodo-3-hexanol (str&cond)

2. Alcohol + hydrogen halide  alkyl halide + water ROH + HX  RX + H 2 O React methanol with hydrogeniodide (str, cond, name product) CH 3 -OH + HI  CH 3 -I + H 2 O

React 2-pentanol with Hydrogen Fluoride (str, cond, name product)

3. Dehydration of alcohols to form alkenes Alcohol –H 2 SO 4  alkene + H 2 O Dehydrate 2-butanol (str&cond) OH C-C-C-C –H 2 SO 4  C=C-C-C + H 2 O

Reaction Mechanism for Dehydration of Alcohols H C-C-OH + H +  C-C-O-H + H C-C-O-H +  C-C + + H 2 O C-C +  C=C + H + H Indicated Protonated Alcohol

Protonated alcohol – an alcohol where a H + bonds coordinately to the hydroxyl group giving the alcohol a positive charge

4. Alcohol + metal  alcohol salt + H ROH + M  RO - M + + ½ H 2 *M = Na +, K +, Ba +2, Ca +2, Mg +2, Al +3

React ethanol with Barium C-C-OH + Ba  (C-C-O -1 ) 2 Ba +2 + H 2 Condensed:

1.Name Metal 2.Prefix for # of C’s and follow with – oxide (C-C-O -1 ) 2 Ba +2 = barium ethoxide

React pentanol with lithium (str, cond, name product) 2-C-C-C-C-C-OH + 2Li  2C-C-C-C- C-O -1 Li + + H 2 (Coefficient for H 2 groups at the end) Condensed: Name:

React methanol with Al (str, cond, name product)

Synthesize barium octoxide (cond.)

5. Alcohol + metal hydroxide  alcohol salt + water ROH + M +1 OH -1  RO - M + + H 2 O React ethanol with lithium hydroxide (str,cond, name product) C-C-OH + LiOH  C-C-O -1 Li + + H 2 O Lithium ethoxide

React propanol with Mangesium hydroxide [Mg(OH) 2 ] (balance it) React pentanol with aluminum hydroxide (balance it) Form barium nonoxide 2 ways (condensed)

General form: ArOHC 6 H 5 OH Nomenclature: Orthobromophenol or 2-bromophenol (-OH = #1 position) 2,3 – dibromophenol

ArCl + H 2 O or NaOH  ArOH + HCl or NaCl Synthesis of phenol: ArH + Cl 2 –FeCl 3  ArCl + HCl ArCl + H 2 O or NaCl  ArOH + HCl or NaCl Do synthesis structurally

1.Halogenation: ArOH + X 2 –FeX 3  ArXOH + HX Form 2,4-diiodophenol

2. Nitration: ArOH + HNO 3 –H 2 SO 4  ArNO 2 OH + H 2 O Form 2,3,5-trinitrophenol

3. Friedel-Crafts Alkylation: ArOH + RCl –AlCl 3  ArROH + HCl Form metapropylphenol

4. Phenol + metal  phenol salt + hydrogen ArOH + M  ArO -1 M + + ½ H 2 React phenol with Lithium (need 2 rxn groups to make H 2 )

5. Phenol + metal hydroxide  phenol salt + water ArOH + M + OH -  ArO - M + + H 2 O React phenol with barium hydrxide

Synthesize aluminum phenoxide (str&cond) 1. + Cl 2 –FeCl 3  + HCl 2. + H 2 O or NaOH  + HCl or NaCl

Either… Al  2 ( O - ) 3 Al H Al(OH) 3  ( O - ) 3 Al H 2 O