p-Toluenesulfonic acid → HCID 86759330, compound

Participants

Reaction Steps

A 250 ml round-bottomed flask was loaded with 6.64 g of amidine A lactam 15d (15.5 mmol) and 150 ml of dry CH2Cl2. 11.55 g of p-toluenesulphonic acid hydrazide (62.0 mmol) were then added followed by 1.47 g of TsOH (7.75 mmol). The solution was stirred at room temperature for 44 h. After the addition of 150 ml of CH2Cl2, the solution was washed three times with water and adjusted to a pH of >12 by addition of 2M NaOH. The combined wash solutions were extracted with 100 ml of CH2Cl2 and the combined organic phases dried over MgSO4. After filtration, the solvent was removed under reduced pressure and the resulting residue was purified by means of chromatography (5.2×20 cm silica gel, eluent: CHCl3/MeOH 30:1) to afford 4.96 g of 15e (86%), which is sufficiently pure for further reactions. An analytical sample was obtained by crystallization from THF/cyclohexane.

Provenance & Evidence