Organic Chemistry

  Several simple rules allow us to draw proper Lewis structures: Rule (1)   (1) Lewis structures show the connections between atoms in a molecule or ion using only the valence electrons of the atoms involved. Valence electrons are those of an atom’s outermost shell. Rule (2)   (2) For …

  The Relative Stabilities of Cycloalkanes: Ring Strain ** Cycloalkanes do not all have the same relative stability. Experiments have shown that cyclohexane is the most stable cycloalkane and that, in comparison, cyclopropane and cyclobutane are much less stable. This difference in relative stability is due to ring strain, which comprises …

  Conformational Analysis of Butane ** Now let us consider rotation about the C2—C3 bond of butane. The barriers to rotation about the C2—C3 bond in butane are larger than for rotation about the C—C bond in ethane, but still not large enough to prevent the rotations that lead to …

    Two groups bonded by only a single bond can undergo rotation about that bond with respect to each other: ** The temporary molecular shapes that result from such a rotation are called conformations of the molecule.   ** Each possible structure is called a conformer.   ** An analysis of the …

  What is Cycloalkanes? ** Saturated cyclic hydrocarbons are called cycloalkanes, or alicyclic (aliphatic cyclic) compounds, and have the general formula (CH2)n or CnH2n.  ** Cycloalkanes are named by adding “cyclo” before the parent name of alkane.   ** Substituted cycloalkanes are named by rules similar to those for open chain …

  What is Alkanes ? ** Alkanes are saturated hydrocarbons; that is, they contain only carbon-carbon single bonds. ** In this context, saturated means that each carbon has the maximum number of hydrogens bonded to it.   Nomenclature of Alkanes The IUPAC System ** Ideally, every organic compound should have a …

  What is Alkanes ? ** Alkanes are saturated hydrocarbons; that is, they contain only carbon-carbon single bonds. ** In this context, saturated means that each carbon has the maximum number of hydrogens bonded to it.   ** We often refer to alkanes as aliphatic hydrocarbons because the physical properties of …

  Functional Groups ** Carbon combines with other atoms (e.g., H, N, O, S, halogens) to form structural units called functional groups. ** Functional groups are important for three reasons. First, they are the units by which we divide organic compounds into classes. Second, they are sites of characteristic chemical …