Organic Chemistry Notes 1 - DOC by yso58733


									Organic Chemistry Notes

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

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
                    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

         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-

          o iso-propyl           CH3CH-

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

          o tert-pentyl          CH3CH2C-

      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
    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”)

        Class                             General Formula        Example
       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

       Example:           CH3
                         CH3 – CH – CH2 – CH – CH – CH3
                                      OH OH
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

      Example:                    Cl
                                  Cl – C – CH3

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

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