Organic preparations / Conrad Weygand ; translated and revised from the German text.

  • Conrad Weygand
Date:
1945
Catalogue details

Licence: In copyright

Credit: Organic preparations / Conrad Weygand ; translated and revised from the German text. Source: Wellcome Collection.

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    The preparation of an organic compound may be achieved in different ways, depending upon the starting material and upon the chemical nature of the desired product. Two special cases can be distinguished: 1. The reacting compounds in one case exhibit such preference to react with each other in only one way that the process proceeds in one direction only. Even under very different conditions, and therefore with varying velocity, the same reaction products are obtained. In this case, the success of the synthesis depends primarily on the preparation of the starting materials. 2. In the second case, several different reactions compete with each other, thus inevitably forming a mixture of reaction products. The suc- cess of the preparative work depends on directing the'reaction by the choice of suitable conditions (temperature, pressure, radiation) and reagents (solvents, catalysts) so that the desired product is formed in optimum yield and is accompanied only by by-products from which it can be conveniently separated. The reactions of the first type are marked by the presence of so called key elements »which easily break their bond with carbon in favor of an- other, especially an ionic bond.
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