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The synthesis of 1,1-diphenylethylene (DPE) via a Grignard reaction, followed by an acid-catalyzed dehydration reaction, yields a mixture of compounds. DPE is a high boiling liquid that cannot be purified using simple distillation. However, it is easily separated from the more polar starting material and intermediate alcohol using both thin layer and column chromatography. Second-semester organic chemistry laboratory students learn the techniques of running reactions under anhydrous conditions and of column chromatography. In addition, the experiment demonstrates clearly the relationship between thin layer and column chromatography.

An experiment has been developed to help students understand the mechanism of the metathesis reaction. Students get the opportunity to gain experience performing reactions in an area of chemistry that is at the forefront of modern research. The products of reactions executed in one class can be used as starting materials by students in another class.

A two-step sequence has been developed to demonstrate key chemical reactions to students in introductory organic laboratory. By producing crystals in a dramatic manner, the experiment catches students' attention. The procedure requires a short setup time, and the materials are left in the laboratory for a week. Crystals will grow from the bottom of a flask like stalagmites.

Asymmetric hydrogenation of dibenzoyl-difluoro�methane has been studied for the first time. In contrast to �BINAL-H, baker’s yeast and CBS reduction procedures, ruthenium-catalysed hydrogenation using axially chiral diphosphine ligands provides excellent yield, diastereoselectivity and good enantioselectivity (up to 72% ee). Enantiomer enrichment by recrystallisation allows for the pure fluorinated diol to be isolated as a single enantiomer in moderate yield. [ABSTRACT FROM AUTHOR]

A study on the enantioselective hydrogenation of tertiary alkyl ketones catalysed by a novel class of tridentate-Ru complex is reported. In contrast to the extensively studied [RuCl(2)(diphos)(di-primary amine)] complexes, this new class of hydrogenation catalyst smoothly reduces these less reactive bulky ketones with up to 94 % ee. The same catalyst system can also selectively reduce other potentially problematic substrates such as bulky heterocyclic ketones. Unusually for a pressure hydrogenation catalyst, similar enantioselectivity can be obtained under transfer hydrogenation conditions. The transfer hydrogenations are somewhat slower than the pressure hydrogenations, but this drawback is readily overcome, since we have discovered that a microwave accelerated transfer hydrogenation of the above ketones occurs within 20 min at about 90 degrees C with similar selectivity to that obtained in the pressure hydrogenation system.