Sonochemistry Quo Vadis

Some readers may be suq rised by the absence of conclusions at the end of each chapter. A reason for this is that we felt that it would be more important to try to draw a general view on sonochemistry in light of the data accumulated while giving a few prospective ideas on what sonochemistry can be in the coming years. Fragmented conclusions which would apply only to restricted domains were thus replaced by these final considerations. 

In 1990, sonochemical effects were classified on the basis of a tentative physical picture of the activation by ultrasound. As emphasized in the original and subsequent reports, any systematization has its own strengths and weaknesses and we can, from the start, recall some of the present ones. 

Since the publication of these guidelines, no obviously conflicting result has been reported. On the contrary, some mechanistic investigations have shown the occurrence of ET processes in reactions where they were a priori less probable, but suspected from a sensitivity to sonochemical effects. In a number of other cases, no valuable interpretation can be proposed for the sonochemical effect (e.g., the hydroboration reaction, p. 84). 

Weaknesses exist, arising from the fragmented knowledge of sc ne basic phenomena. Chapter 1 in this book shows that many physical aspects of cavitation still await clarification. Any breakthrough in terms of the physical picture of cavitation should, therefore, allow a more accurate formulation or a correction of the rules. 

Einhom, C. Einhom, J. Sinisterra-Gago, J.V. Tetrahedron Lett 1990,31,4125-4128. 

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M. Chanon and J.L. Luche, Sonochemistry Quo Vadis, in J.L. Luche (Ed.), Synthetic Organic Chemistry, Plenum Press, New York, 1998. 

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