Lab

Objective To learn steam-distillation and vacuum-distillation techniques to produce an essential oil from a plant raw material (orange peel). Background Limonene, a compound of the terpene family, is present in the essential oil of citrus peel. The limonene structure has a chiral center, and thus it is found in nature as two enantiomers the (R)- … Read more

Objective To synthesize a heterocyclic compound (triphenylpyridine) by a sequence of reactions involving an aldolic condensation, a Michael addition, and a final condensation reaction to yield a pyridine ring. Background The aldol condensation reaction produces β-hydroxyaldehyde (aldol) or β-hydroxyketones from two carbonylic compounds with at least a hydrogen atom at the α-position with respect to … Read more

Objective To produce a derivative of uridine and use chromatographic techniques for their identification and isolation. Background Recent advances in the pharmaceutical industry have increased interest in the chemistry of nucleic acids for example, the synthesis of AZT (3′-azido-2′,3′-dideoxythymidine) used in treating AIDS. Furthermore, the multistep synthesis of these products requires the application of various … Read more

Objective To extract essential oils from cinnamon and/or cloves by hot extraction using an organic solvent under reflux and then removing the solvent under reduced pressure (rotary evaporator). Background Many plants are commonly used for their pleasant fragrances or flavors caused by the presence of certain molecules that provide them with their organoleptic properties. The … Read more

Objective The synthesis of isopropylidene-α-D-glucofuranose, is approached to familiarize the student with some of the most common functional group protection reactions in carbohydrate chemistry. That is, the protection of hydroxyl groups. 3D Structure Background Carbohydrates are compounds characterized by having several hydroxyl groups that give characteristic reactions of alcohols. The key step for the synthesis … Read more

Objective The purpose of this practice is to obtain an asymmetric ether of industrial interest from naphthalen-2-ol (β-naphthol) using the Williamson synthesis. Background Ethers can be obtained from alcohols by nucleophilic substitution reactions (SN2). The Williamson synthesis is a process that allows the preparation of a wide range of ethers, both symmetrical and asymmetrical, as … Read more

Objective The purpose of this experiment is to study the oxidative cleavage of a double bond. Background Potassium permanganate, KMnO4, is an oxidant commonly used in organic chemistry. In this practical, it will be used to produce the oxidative cleavage of a double bond to obtain two carboxylic groups at the ends of the bond. … Read more

Objective The purpose of this practice is to obtain a simple nitrogenous heterocycle, in this case a triazole (five-membered ring with three nitrogens) fused to a six-membered aromatic ring, benzotriazole. Background Benzotriazole is a heterocyclic compound that is used as a starting product in the manufacture of some pharmaceuticals, in photography as a component of … Read more

Objective The purpose of this experiment is the performance of an electrophilic aromatic substitution reaction (SEAr), such as the nitration of methyl benzoate. Background An example of an electrophilic aromatic substitution reaction (SEAr) is the nitration of an aromatic ring, using the nitronium ion, ⊕NO2, as an electrophile. The methoxycarbonyl group of methyl benzoate deactivates … Read more

Objective Isolation of caffeine from soluble coffee (from a commercial product), by extraction with an organic solvent and separation by centrifugation of the aqueous phase and the organic phase obtained. Background Caffeine is a naturally occurring alkaloid (xanthine family) found in a wide variety of plants, including coffee beans, tea leaves, cocoa beans, and kola … Read more