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A majority of chemistry graduates seek employment in a rapidly changing chemical industry. Our attempts to provide the graduates with skills in entrepreneurship and the ability to understand and communicate with their chemical engineering colleagues, in addition to their fundamental knowledge of chemistry, are described. This is done at second-year level with practical projects in which student teams formulate and prepare relatively simple chemical products for marketing, followed a year later by a more advanced study of the feasibility of producing and marketing a fine chemical on a commercial scale. (Contains 1 note.)

Kinetics experiments are used to establish the free energy, enthalpy, and entropy of activation for the enantiomerization of three structural classes of 2-lithiopyrrolidines. It is found that alpha-aminoorganolithiums chelated by a N-methoxyethyl or N-Boc group have a barrier to enantiomerization 2-3 kcal/mol lower than that of unstabilized alpha-aminoorganolithiums at 273 K.

Cases are presented to illustrate the effects of these dysfunctional attitudes and therapeutic approaches toward them. Cognitive, behavioral, and dynamically oriented interventions are presented which have been effective when a child's difficulties result from his acting in accordance with the family's attitude toward learning. (Author)

The tin-lithium exchange reaction is occasionally unpredictable appearing facile in some situations and impossible in apparently similar compounds. However the configurational and conformational effects play a role in the rate of tin-lithium exchange in [alpha]-aminoorganolithiums in addition to the well-established thermodynamic effects.

¹H NMR-based kinetic studies have revealed the latent mechanistic complexity of deceptively simple hydrochloric acid-catalyzed reactions of salicylaldehyde-derived Baylis-Hillman adducts. Reactions conducted at 0℃ afforded 2-(chloromethyl)cinnamic acid derivatives as the major products and the corresponding 3-(chloromethyl)coumarin derivatives as the minor products. In reactions conducted in refluxing acetic acid, however, the 3-(chloromethyl)coumarin derivatives are the sole products. Variable-temperature 1H NMR analysis permitted the determination of the rate constants and kinetic parameters involved in the pseudo-first-order formation of (Z)-2-(chloromethyl)-3-(2-hydroxyphenyl)-2-propenoic acid. The kinetic data clearly preclude the operation of classical kinetic versus thermodynamic control and indicate the operation of three independent reaction pathways. Theoretical studies of these pathways undertaken at the B3LYP/6-31G(d) level permitted rationalization of the experimental data and provided insights into the possible mechanism of the enzymic E-Z isomerization and cyclization of (E)-cinnamic acid analogues to afford coumarins. [ABSTRACT FROM AUTHOR]

The relative merits of two different Baylis–Hillman approaches toward the preparation of coumarin derivatives, containing peptide-like side chains, have been explored. In one approach, use of methyl acrylate as the activated alkene requires a protecting group strategy, an approach that is not necessary when usingtert-butyl acrylate. [Supplementary materials are available for this article. Go to the publisher's online edition ofSynthetic Communications® for the following free supplemental resource(s): Full experimental and spectral details.] [ABSTRACT FROM AUTHOR]

Rapid, microwave-assisted Baylis-Hillman reactions of substituted salicylaldehydes, followed by one-pot hydrogen iodide-mediated cyclization and reduction of the corresponding adducts, has afforded 3-methylcoumarins in up to 94% yield in the final step. Subsequent microwave-assisted selenium dioxide oxidation of selected 3-methylcoumarins has provided convenient access to the corresponding coumarin-3-carbaldehydes and permitted a significant improvement over the yield obtained using conventional heating. [image omitted] [ABSTRACT FROM AUTHOR]