Scheme 2
From: Rapid one-pot radiosynthesis of [carbonyl-11C]formamides from primary amines and [11C]CO2
Radiolabelling of [carbonyl-11C] formyl methionine tBu ester ([11C]15) and subsequent deprotection to form [carbonyl-11C] formyl methionine ([11C]16). Reaction conditions: a methionine tBu ester (4.7 μmol, 1 equiv.), BEMP (34.6 μmol, 7.4 equiv.), diglyme (75 μL), [11C]CO2, 0 °C, 2 min, then POCl3 (54.05 μmol, 11.5 equiv.) in diglyme (75 μL), 0 °C, 2 min. b NaBH4 (2.67 mg, 15 equiv.), diglyme (50 μL), 0 °C, 10 min. c TFA (200 μL), 20 °C, 2 min