Fischer esterification can be a time-consuming process, requiring days for a reaction to reach equilibrium. In this article, researchers developed a way to hasten this process by using a specially designed microwave to heat the reaction quickly and evenly and at an increased pressure. In order to test the efficiency of the device, they synthesized 2-ethylhexyl benzoate from benzoic acid and 2-ethylhexanol as shown below.

Sulfuric acid as well as para-toluene sulfonic acid (PTSA) were used to catalyze the reaction. In order to shift the reaction towards the products, a large excess of 2-ethylhexanol was used and the water produced was constantly removed. One of the disadvantages of Fischer esterification is that dehydration can also occur, resulting in unwanted ether and alkene products. Because of this, the temperature and catalyst concentration must be carefully monitored. The researchers were able to show that microwave heating causes no ill effects on the reaction and reduces the time required to a matter of minutes while still producing a high level of the desired product.

A traditional method for the reduction of alkynes to trans-alkenes is to dissolve metal reduction using sodium or lithium in ammonia. However, we can also use Zinc as a metal to reduce alkynes.

In this specific case, by changing the proton source in the reaction, the dissolving Zinc metal reduction of ethyl phenylpropiolate to the corresponding cinnamate ester can be stereochemically controlled.

The product of the reaction will be a mixture of cis and trans ester. By this reaction, we can see the efficiency of Zinc in the reduction of alkynes.