TCMDC_ArylPyrrole

 

SM recovered.

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Hydrolysis of PMY 27-1 to give the antipyrine glycanamide for coupling to pyrrole acid core. According to literature reference selective hydrolysis with catalytic base is successful, but not yield given.



Reaction Start Time: 09.40 12/12/11
PMY 27-1 (140 mg, 0.38 mmol, 1 equiv.) was stirred in PhMe (20 mL) and heated to reflux. Partial solution. Sodium hydroxide (22 mg, 0.55 mmol, 1.4 equiv.) was added. After 2 hours, TLC shows no reaction. Water (appox. 1 mL) was added. Reaction mixture turns clear then hazy again. After 4 hours (13.40), reaction is a clear solution again. TLC shows conversion to a new product by vanillin dip (overlapping Rf). At 7 hours (16.30), TLC shows SM still remaining. Reaction cooled to room temperature and stored at -20 °C.fumehood shutdown required for 13/12/11. 0900 15/12/11 Reaction reheated to reflux, still colourless. Still not complete by TLC at 1600 15/12/11. Reaction cooled 0930 16/12/11. TLC shows no change. White crystals form on cooling. Filtered and dried under vacuum (62 mg). ¹H NMR consistent with PMY 27-1. Filtrate washed with water (2 × 10 mL), brine, dried (MgSO₄) and concentrated to a yellow oil (20 mg). Consistent with SM by ¹H NMR.

TLC (10% MeOH/DCM) visualised with UV and vanillin:


NMR:


Reference:
J. Chem. Pharm. Res., 2010, 2(4):410-41

See also:
Coupling of hippuric acid and 4-aminoantipyrine using T3P (PMY 27-1)
Synthesis of hippuric acid (PMY 26-1)

Risk and Hazard Assessment: