21. The picture on the right shows a fractured acetal joint in a water supply system. 22. Modern harpsichords frequently employ plectra made with plastic, specifically the plastic known as acetal . 23. The asymmetric diol is first treated with a tin reagent to produce the dibutylstannylene acetal . 24. It is the dimethyl acetal of formaldehyde. 25. Following the formation of the oxazolinium ion intermediate, water attacks the electrophillic acetal carbon. 26. A Dupont acetal polymer, Delrin was introduced as the D'Andrea Delrex line. 27. A polymer packing ring and a guide ring is attached with the Acetal guide bush. 28. This acetal is a principal flavour compound in sherry, and contributes fruitiness to the aroma. 29. To increase yields of ketals or acetals , water formed during the reaction can be removed. 30. Acetals are stable compared to hemiacetals but their formation is a reversible equilibrium as with esters.
