A novel experiment is described in which solvated electrons in liquid ammonia reduce a benzyl alcohol carbon without affecting the aromatic ring. The reductive activity of solvated electrons can be partially or completely quenched through the addition of electron scavengers to the reaction mixture. The effectiveness of these scavengers was found to qualitatively correlate with their electron affinities obtained from first-principles electronic-structure calculations. The reaction completion is monitored using 13C NMR spectroscopic analysis of the whole reaction mixture, without separation and purification. This interesting, dynamic, and diverse experiment combines a classical synthetic procedure, NMR spectroscopy, and molecular modeling and is suitable for second-year through fourth-year chemistry and biochemistry majors.

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Letters Markovnikov's RuleThe recent contribution by Ilich, Rickertsen, and Becker (1) provides abundant reasons for abandoning the description of addition reactions and their products as "Markovniknov" or (even worse) "anti-Markovnikov". In a recent review (2) I have surveyed the history of this usage and concluded that its use in teaching has long outlived its utility. The deeper understanding of these reactions as involving appropriate reactive intermediates (e.g., carbocations), whose relative stabilities can be understood on a general basis, should have superseded the use of an empirical rule that is often inapplicable, often restated in ways unrecognizable to its originator, and never an adequate substitute for understanding. If we wish students to understand organic reactivity as a whole, we should not provide them with this cognitive crutch. If our use of the description of one product as a "Markovnikov product" is meant to honor a great 19th century chemist, what is the effect of describing another as an "anti-Markovnikov product"? Unfortunately, the authors of the article draw back from the simple conclusion that the rule should be abandoned, but rather attempt once again to restate or reformulate it, while clinging to the name. In agreement with Gooch (3), I urge teachers and textbook authors to move past Markovnikov's rule once and for all. The author replies: Literature CitedThe principal goal of our work published in this Journal (1) has been to show that electrophilic addition reactions to alkenes can be adequately described by the standard parameters of chemical reactivity: charge distribution of the substrate and energy of the reaction-determining intermediate. Through the analysis of six representative addition reactions we also show that the term "anti-Markovnikov" is incorrect and redundant. Dr. Kerber's plea-and the stronger message of his article published in Foundations of Chemistry (2)-is to avoid artificial and non-pedagogical extensions of the Markovnikov rule and phase it out from organic chemistry textbooks. We completely agree with and support Dr. Kerber's call for making teaching and learning of second-year organic chemistry more accurate, more effective, and less difficult.However, beyond undergraduate chemistry courses and textbooks there is a vast and very important world of practicing organic chemists. They keep using the "Markovnikov terminology" as useful shorthand for classification of products in an ever-increasing number of what seem to be electrophilic addition reactions. We posit that the use of this terminology is often incorrect. Our extensive analysis (submitted for publication) of the energy-charge profile of a number of reactions reported as "anti-Markovnikov" suggest that they follow mechanisms different from those of the reactions originally described some 140 years ago by Vladimir Markovnikov. However, we also feel that more insight into the mechanisms of addition reactions to alkenes is needed before requesting radical changes in the organic chemistry terminology...

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