1. Introduction

The growing awareness that a serious damage to the environment had been caused and valuable resources consumed stirred up the social and political conscience and preservation of the environment became one of the key issues in the political arena during the 1960s. What impressed more common people was the destruction of the ecosystem by strongly toxic compounds used e.g. as pesticides in agriculture or for new commodities, e.g. polymers. Large amounts of aggressive products and intermediates were buried in chemical plants, and leakage from such deposits may cause pollution of water bodies. In the following decades, the reversed point of view was introduced, focusing on a new way of preparing useful chemicals while avoiding to produce toxic by-products. This was tagged Green Chemistry and found a meaningful expression in the 12 green chemistry principles.