An experiment for the undergraduate organic chemistry laboratory involving a method for the isolation of eugenol from cloves has been developed. The experiment employs microwave-assisted extraction (MAE) of the essential oil from whole cloves using aqueous ethanol and the subsequent isolation of eugenol by acid-base extraction. The MAE allows for…

Students are introduced to spectrophotometry in comparing the antioxidant activity of pure eugenol and oil of cloves from a commercial source using a modified ferric reducing antioxidant power (FRAP) assay. The extraction of the essential oil from dried cloves is demonstrated to facilitate discussions on green chemistry. The anesthetic properties…

Natural products are ubiquitous in nature but do not form a large proportion of the A-level syllabuses in the UK. In this article we briefly discuss a small selection of natural products, focusing on alcohols, aldehydes and ketones, and alkaloids. We then outline two natural product experiments that are suitable for A-level chemistry clubs or…

Natural product isolation and analysis provide an opportunity to present a variety of experimental techniques to undergraduate students in introductory organic chemistry. Eugenol, anethole, and carvone were extracted from six common spices using steam-distillation and diethyl ether as the extraction solvent. Students assessed the purity of their…

Vanillin, the compound responsible for the well-known vanilla aroma, is almost exclusively produced via a chemical process, with only a small fraction extracted from natural sources, namely, the bean of the orchid "Vanilla planifolia". Research is being done towards a green chemistry process to obtain natural vanillin. A model biotechnological…

An ozonolysis experiment, suitable for undergraduate organic chemistry lab, is presented. Ozonolysis of eugenol (clove oil), followed by reductive workup furnishes an aldehyde that is easily identified by its NMR and IR spectra. Ozone (3-5% in oxygen) is produced using an easily built generator. (Contains 2 figures and 1 scheme.)

The use of an olfactory acid-base indicator in titrations for visually impaired students is discussed. Potential olfactory indicators include eugenol, thymol, vanillin, and thiophenol. Titrations performed with each indicator with eugenol proved to be successful. (KR)

Describes two procedures for the conversion of eugenol to vanillin

Describes a natural-products experiment involving steam distillation, solvent extraction, and spectroscopic identification. (MLH)

Olfactory titrations using raw onions and eugenol as acid-base indicators are reported. An in-depth investigation on olfactory titrations is presented to include requirements for potential olfactory indicators and protocols for using garlic, onions, and vanillin as acid-base olfactory indicators are tested.

A description is given of work undertaken to develop a simple, specific, and reliable method for ozone. Reactions of ozone with several 1-alkenes were studied at room temperature (25C). Eugenol (4-allyl-2-methoxy phenol), when reacted with ozone, was found to produce relatively large amounts of formaldehyde as compared to other 1-alkenes tested.…

Describes laboratory procedures, demonstrations, and classroom materials, including "diet poker" (nutrition game); an experiment on enzyme characteristics; demonstrations of yeast anaerobic respiration and color preference in Calliphora larvae; method to extract eugenol from clove oil to show antibiotic properties; and Benedict's test.…

A modified experimental procedure for the one-step synthesis that is suitable for the undergraduate organic lab is presented. In the course of work towards the more routine use of air-sensitive organometallic complexes such as the Grubb's catalyst, the natural product (E)-4-(4-hydroxy-3-methoxyphenyl) but-2-en-ol, 4, was synthesized.

Blocking occurs when previous training with a stimulus A reduces (blocks) subsequent learning about a stimulus B, when A and B are trained in compound. The question of whether blocking exists in olfactory conditioning of proboscis extension reflex (PER) in honeybees is under debate. The last published accounts on blocking in honeybees state that…