A) Identify the amine functional group from the compound? B) Identify the alcohol functional group from the compound?

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1 Answer
Jul 10, 2017

These are just functional groups you'll have to know and memorize.

#(1)# is a hydroxy group, i.e. alcohol functional group.
#(2)# is a benzene ring. If attached to something else, it could be called a phenyl group, #"Ph"-#, or #"C"_6"H"_5-#.
#(3)# is a secondary amine group.
#(4)# is an acyl group, seen in ketones, aldehydes, carboxylic acids, acyl chlorides, anhydrides, and esters. Get to know this group.


An amine group is #-"NR"_2#, where #R# can be alkyl, aryl, etc. So, you could have

  • #-stackrel("H")stackrel(|)"N"-"H"# (primary amine)
    #color(white)(.,)ddot#

  • #-stackrel("R'")stackrel(|)"N"-"H"# (secondary amine)
    #color(white)(.,)ddot#

  • #-stackrel("R'")stackrel(|)"N"-"R''"# (tertiary amine)
    #color(white)(.,)ddot#

  • #-stackrel("R'")(stackrel(|)("N"^(+)))-"R''"# (quaternary ammonium salt)
    #color(white)(....)|#
    #color(white)(.,)"R'''"#

And an alcohol group could be:

  • #-stackrel("H")stackrel(|)"C"-ddot"O"-"H"# (primary alcohol)
    #" "| color(white)(.-)ddot#
    #color(white)(..)"H"#

  • #-stackrel("R")stackrel(|)"C"-ddot"O"-"H"# (secondary alcohol)
    #" "| color(white)(.-)ddot#
    #color(white)(..)"H"#

  • #-stackrel("R")stackrel(|)"C"-ddot"O"-"H"# (tertiary alcohol)
    #" "| color(white)(.-)ddot#
    #color(white)(..)"R'"#

Of course, all of these bond angles are based on the tetrahedral electron geometry.