Organic Chemistry Notes 1 - DOC by yso58733

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									Organic Chemistry Notes

Hydrocarbons:      compounds containing C and H (and sometimes O, N, or
halogens)

Alkanes:   carbon atoms bonded together with single bonds, saturated
hydrocarbon (no multiple bonds)
    Nomenclature
         o Suffix: -ane
         o Prefixes (these apply to all organic molecules, not just alkanes)
                    # of carbons in a
                                                 Prefix
                    continuous chain
                            1                    Meth-
                            2                     Eth-
                            3                    Prop-
                            4                     But-
                            5                    Pent-
                            6                     Hex-
                            7                    Hept-
                            8                     Oct-
                            9                     Non-
                           10                     Dec-
    Structures




      Notation:
         o Two-dimensional structural formula: shows all bonds




         o Condensed structural formula: does not show H bonds, or no bonds
           at all
                        CH3-CH2-CH2-CH2-CH2-CH3
                                    Or
                         CH3CH2CH2CH2CH2CH3
                                    Or
                              CH3(CH2)4CH3

         o Bond-line structural formula:  both ends and angles represent C
           atoms where C-H bonds are not shown, but you assume that they
           are saturated, unless otherwise shown




Isomers:     compounds having the same formula, but different structural
formulas; these only occur with chains of 4 or more C; each isomer is a separate
compound with unique properties
    Branched chain: consist of a hydrocarbon with other things besides H
      branching off of the main chain
    Nomenclature of branched alkanes:
         o Locate the longest continuous chain of C atoms
                 What is not part of this chain is a substituent and needs to be
                   added to the name later
         o Number the carbons in the parent chain beginning with the end of
             the chain nearest the substituent.
         o Use these numbers to designate the position of the substituent,
             called an alkyl group
                 The name of the alkyl group is the prefix for the number of
                   carbons with a –yl suffix.
                 Ex.    CH3- as a substituent is called a methyl group
         o Now you have the parts for the name
                 Write down the number of the carbon from which the alkyl
                   group branches
                 Add a hyphen
                 After the hyphen, place the name of the alkyl group
                 Finally, add the name of the parent compound
    When there are two or more alkyl groups:
          o Number carbons so the sum of the total number mentioned (when
              citing the alkyl groups) is the lowest possible
          o When you list the alkyl groups in the name, list them alphabetically
              (ethyl- would come before methyl-)
                   3-ethyl-3-methylhexane
          o When mentioning multiple alkyl groups that are identical, add a
              prefix (di-, tri-, tetra-, penta-) in front of the alkyl group name
                   Ex. 2,2,3-trimethylbutane
Practice Problems:
   1. List the two isomers of C4H10.




                        Butane                  2-methylpropane

   2. List the 9 isomers of C7H16. Name them as you go to eliminate duplication.




HWK: Alkanes Practice
     p. 1045 #13, 17-21 odd           (structures & nomenclature)
Alkane Review:        draw or name the following molecules:




   2,2-dimethylbutane




   4,6-diethyl-4,6,7-trimethyl-5,5-dipropyldecane




   3-ethylpentane




   2-ethyl-1,1,3,3-tetramethylpentane




   2,2,3-trimethyloctane




Complex Alkyl Groups: because of how large some of the alkyl groups get,
some are just given names
      n- before the alkyl group means that it is in a straight line
           o n-butyl             CH3CH2CH2CH2-
           o n-propyl            CH3CH2CH2-
      iso- before the alkyl group means that there is a methyl group attached to
       the branch furthest from the parent chain
           o iso-butyl           CH3CHCH2-
                                    CH3

          o iso-propyl           CH3CH-
                                    CH3

      tert- before an alkyl group means that the carbon that bonds to the
       parent chain bears two methyl groups, as well
                                    CH3
           o tert-butyl          CH3C-
                                    CH3

                                       CH3
          o tert-pentyl          CH3CH2C-
                                       CH3

      All of these alkyl groups are written as follows:
                                 # - prefix – alkyl alkane


Alkenes:   hydrocarbon containing at least one double bond (=), unsaturated
hydrocarbon (has a multiple bond)
    Nomenclature
         o Find the longest continuous chain
         o Name this chain by placing a “-ene” suffix on instead of the “-ane”
         o Indicate the position of the double bond by placing a number of
           the carbon in front
                Ex. 1-butene        CH3CH2CH=CH2
    Multiple double bonds are signified by turning the ending from “-ene” to
     “-diene” or “-triene.” The numbers in front describe where the double
     bonds are in the parent chain.
Alkynes:   hydrocarbon containing at least one triple bond (), unsaturated
hydrocarbon
    Nomenclature
         o Follows the same rules as alkenes, except a “-yne” suffix is used.
           Multiples also follow the same rules as alkenes.


Aromatic: hydrocarbons containing benzene (in the form of a ring), which are
very stable because of delocalized electrons (electrons are free to move
between C atoms)
    We will leave this area to the college profs to teach! 


HWK: p. 1045 #23-28 all       (nomenclature of multiple bonds)
Functional Groups:      groups of atoms other than alkyl groups that are
attached to the parent chain (hydrocarbons containing these groups are
sometimes called “hydrocarbon derivatives”)

                       Functional
        Class                             General Formula        Example
                         Group
                                               R–X
       Halides       – X (Cl, Br, I, F)                            CH3I
                                              R – OH
       Alcohols           – OH                                    CH3OH
                                             R – O – R’
        Ethers            –O–                                   CH3OCH3
                           O                     O
   Aldehydes                                                     CH3CHO
                         –C–H                R–C–H
                           O                     O
       Ketone                                                   CH3COCH3
                          –C–               R – C – R’
                          O                     O
Carboxylic Acids                                                CH3COOH
                        – C – OH            R – C – OH
                          O                     O
        Esters                                                 CH3COOCH3
                        –C–O–               R–C–O–
                                              R – NH2
       Amines             – NH2                                  CH3NH2
* highlighted items are what denotes the functional group in formulas!


Alcohol Nomenclature: (similar to alkenes)
    Add an “-ol” suffix to the root word
    Place a number in front of the root word to show which carbon has the
     alcohol attached.
    For multiples, add a prefix before the “-ol” ending, i.e. “-diol” or “-triol”
    Example:
                          CH3 – CH – CH3        2-propanol
                             OH

       Example:           CH3
                         CH3 – CH – CH2 – CH – CH – CH3
                                      OH OH
                                                              5-methyl-2,3-hexadiol
Halide Nomenclature: (similar to alkyl groups)
    Add a “bromo-,” “chloro-,” “fluoro-,” or “iodo-“
    Put numbers in front of each to show which carbon has the halide
      attached to it.
    For multiples, use the prefixes, i.e. “dichloro-“ or “triiodo-“
    Example:              I             Br
                              CH – CH2 – CH – CH3
                           I
                                                         3-bromo-1,1-diiodo-butane

      Example:                    Cl
                                  Cl – C – CH3
                                   F
                                                     1,1-dichloro-1-fluoroethane

HWK: p.1047 #47,48                   (functional groups)
     Organic Chemistry Packet

								
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