Compound 2 (1 mmol) added to CH2Cl2 (15 mL) was stirred at
0 C and oxalyl chloride (1.5 mmol) was dripped into the mixture
and stirred at room temperature for 6 h. After the reaction, the
solvent and excess oxalyl chloride was evaporated under reduced
pressure. Toluene (15 mL) and KSCN (1.2 mmol) were added to the