Organic Electrosynthesis - Fundamentals and Applications of Organic Electrochemistry - page 260

stream reaches in excess of 100 m s −1 in a
water-solid interface [81].
Figure 6.31 Collapse of cavitation bubble. (a)
Symmetrical collapse of a cavitation bubble in
bulk solution. (b) Asymmetrical collapse of a
cavitation bubble in a liquid-solid interface
Such a mass transfer promotion by
ultrasonication provides an increase in the
current efficiency for a variety of
electrosyntheses. For example, Atobe et al.
reported that a significant ultrasonic effect on
current efficiency was found in the
electrochemical reduction of
p -methylbenzalaldehyde ( Eq. 6.26 ) [82]. As
shown in Table 6.6 , current efficiency for the
reduction of p -methylbenzalaldehyde was
dramatically increased under ultrasonication.
Furthermore, product selectivity for the
hydrodimeric product (D1) was also increased
by ultrasonication, and the effects could be
rationalized experimentally and theoretically as