Figure 5: Study on the dormant period monitored by means of in situ FT-IR analysis.

Conditions of step A: aldehyde 2a (0.10 mmol), TMSCN 3 (2.0 equiv.) and catalyst 1a (2 mol%) in Et2O (5.0 ml) at 25 °C. Water (1–10 mol%) was added at the marked time point (step B). (a) Three-dimensional stack plot of the IR spectra (10 mol% water). (b) Plot of conversion of 2a versus time (1–10 mol% water). See Table 1 for the length of dormant periods.