chapter  5
68 Pages

Microreactor-Controlled Product Selectivity in Organic Photochemical Reactions

I. INTRODUCTION Selectivity in organic phototransformation continues to be one of the main topics of current interest. Of the various approaches to enhance the selectivity use of microreactors to control the reaction pathways has shown considerable promise [1-11]. Microreactors refer to organized and constrained media which provide cavities and/or surfaces to accommodate the molecules of a substrate and allow chemical reaction(s) to occur. The substrate is usually a small molecule of dimensions of several angstroms, and the microreactor is often tens of angstroms or larger. Thus, microreactors are also known as nanoreactors. A combination of microreactor as a medium and light as a reagent potentially offers a new approach toward “clean chemistry.” The implications of this methodology for environmentlly benign synthesis of chemicals are twofold. First, the increased selectivity of the reaction will decrease the production of unwanted side products. Second, in most cases, the use of a microreactor will eliminate the need for expensive and en­ vironmentally toxic solvents.