PREPARATIONS 265 required. Treatment of the crude sodium derivative with a weak acid, e.g., dilute acetic acid, then gives the normal equilibrium mixture of the keto and enol forms. This preparation was discovered independently by Geuther (1863) and by Frankland and Duppa (1865). The reaction was subsequently investigated in detail and so widely extended by Claisen that it has become solely a specific example of the more general process known as the Claisen Condensation.* Claisen showed that an ester under the influence of sodium ethoxide would not only condense with itself (as in the preparation of ethyl acetoacetate), but also with (i) another ester, (ii) a ketone, if of formula RCH 2 COR, (iii) a nitrile, if of formula RCH 2 CN, in each case with the elimination of alcohol. Examples of these modifications are: (i) C 6 H 5 COOC 2 H- HCH 2 COOC 2 H, -.C 6 H 3 COCH 2 COOC 2 H 5- C 2 H 5 OH Ethyl benzoatc Ethyl acetate Ethyl benzoylacetate. (ii) CH
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This note was uploaded on 09/19/2011 for the course CHM 2211 taught by Professor Castalleano during the Fall '06 term at University of Florida.