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A wide variety of -trifluoromethyl esters can be synthesized in two steps starting from monosubstituted malonic esters and dibromodifluoromethane. The product of the first step, a bromodifluoromethyl-substituted malonate, is transformed to the desired final product by use of KF in Me2SO at elevated temperatures. This second step involves both the loss of one ester and halogen exchange and proceeds through an ,/3-unsaturated ester in which two fluorine atoms are bonded to the terminal carbon. or zinc9 complexes. But the analogous Grignard reagent, CF3MgX, is difficult to prepare and gives low yields of (1) Preliminary results of this study were reported; Tetrahedron Lett.

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This brief laboratory safety note describes how electronic cooking thermometers can be used to replace standard mercury thermometers in the undergraduate organic chemistry lab. Various factors, including safety, cost, and ease of use, were considered. The stainless steel thermometer probe connected to a LCD display unit adequately serves multiple purposes in the organic lab while eliminating the hazards associated with the use of mercury thermometers.

In this study of teachers’ beliefs about young people with chronic fatigue syndrome (CFS), Tina Everett and Colette Fulton find that although teachers are very much concerned to give the right sort of support to enable their students to continue their education, there is confusion about the nature, origin and cause of the illness. They recommend that schools are provided with sound scientific and practical information, and that better communication is established between health and education staff for the benefit of students with CFS and their families.

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We have developed a general Grignard procedure for the synthesis of a variety of aliphatic tertiary alcohols, which presents students with an added challenge of product identification. Many organic syntheses in the undergraduate teaching laboratory can be infused with an extra element of discovery simply by not revealing the specific starting materials. Substitutions of isomers or homologues for the prescribed organic reagents create multiple possibilities for unknowns. We have found inclusion of this type of puzzle helpful in combating the tendency of students to approach lab work in a mechanical or cookbook fashion (1, 2).Five articles on Grignard reactions have appeared in this Journal in the last 10 years (2-6). All organic laboratory manuals include at least one Grignard procedure. Phenylmagnesium bromide is the most commonly described Grignard reagent, used in the synthesis of triphenylmethanol (trityl alcohol) and benzoic acid (7-9). Our variation of the standard Grignard reaction incorporates anhydrous techniques, distillation, and infrared analysis to identify an unknown product. ExperimentalProcedure 1 CAUTION: The organic reagents and products in this procedure are flammable. Diethyl ether is highly flammable. Flame drying of glassware should be completed by all students before diethyl ether is dispensed! RX + Mg → [RMgX] + R′R″C=O → [RR′R″COMgX] → RR′R″COH Criteria: RX = C 2 -C 5 1° alkyl bromide (unbranched) R′R″C=O = C 3 -C 5 ketone RR′R″COH = C 6 -C 9 3° alcohol {R, R′, R″ may be the same or different}