Alkynes can be prepared by the elimination of HX from alkyl halides in a similar manner as alkenes (Section 8.1). Treatment of a 1,2-dihaloalkane (called a vicinal dihalide) with an excess amount of a strong base such as KOH or NaNH2 results in…
Alkyne nomenclature follows the general rules for hydrocarbons discussed in Section 3.4 and Section 7.3. The suffix -yne is used, and the position of the triple bond is indicated by giving the number of the first alkyne carbon in the chain. Numbering the main chain…
Figure 9.1 Synthesizing organic compounds is like conducting a musical group. When in tune, chemists can create highly complex organic compounds. (credit: modification of work “Jazz great visits Navy” by U.S. Navy, Michael Worner/Wikimedia Commons, Public Domain) Chapter Contents 9.1 Naming Alkynes 9.2 Preparation of…
With the background needed to understand organic reactions now covered, this chapter has begun the systematic description of major functional groups. Alkenes are generally prepared by an elimination reaction, such as dehydrohalogenation, the elimination of HX from an alkyl halide,…
Ever since its discovery in Persia around 1000 A.D., it has been known that steam distillation, the distillation of plant materials together with water, produces a fragrant mixture of liquids called essential oils. The resulting oils have long been used as…
The reaction discussed in the previous section involves an addition to an achiral reactant and forms an optically inactive, racemic mixture of two enantiomeric products. What would happen, though, if we were to carry out the reaction on a single…
Most of the biochemical reactions that take place in the body, as well as many organic reactions in the laboratory, yield products with chirality centers. For example, acid-catalyzed addition of H2O to 1-butene in the laboratory yields 2-butanol, a chiral…
The same high reactivity of radicals that enables the alkene polymerization we saw in the previous section also makes it difficult to carry out controlled radical reactions on complex molecules. As a result, there are severe limitations on the usefulness…
form a polymer. Many substituted ethylenes, called vinyl monomers, also undergo polymerization to yield polymers with substituent groups regularly spaced on alternating carbon atoms along the chain. Propylene, for example, yields polypropylene, and styrene yields polystyrene. When an unsymmetrically substituted…
Yet another kind of alkene addition is the reaction with a carbene to yield a cyclopropane. A carbene, R2C:, is a neutral molecule containing a divalent carbon with only six electrons in its valence shell. It is therefore highly reactive and generated only…