4-Aminobenzoic Acid → HCID 136057403, compound

Participants

Reaction Steps

N2-iBu-6-formylpterin (25) 4.0 gm, 15 mmole) was suspended in MeOH. To this suspension was added 4-aminobenzoic acid (2.1 g, 15 mmole) followed by stirring for 10 minutes. The reaction mixture was then cooled in an ice bath with continuous stirring. A solution of pyridinium para-toluene sulfonate (PPTS, 1 M in MeOH, 15 ml, 15 mmol) was added in one portion, followed by the addition of pyridine-borane complex (1.9 ml of 8M solution, 15 mmol) dropwise over a period of 10 minutes. The ice bath was removed, and stirring was continued at room temperature for 3 hours. The fine precipitated product was collected by centrifugation and washed with a 1:1 mixture of hexanes—MeOH several times, and finally with MeOH. The product was dried in vacuum over P2O5 for 24 hours to give light cream-colored powder, yield=5.3 gm, 91%. 1H NMR (DMSO): δ8.87 (s, 1H), 4.62 (s, 2H), 2.75-2.82 (m, 1H), 1.13, 1.16 (2 s, 6H); MS, m/z, M−H+=383 for C18H18N6O4.

Provenance & Evidence