2-Methylpyrrole → Dipyrromethane

Participants

Reaction Steps

Then 200 mL of CH2Cl2 was added to the reaction mixture and diluted, then rinsed by NaOH aqueous solution. Solvent was removed using a rotary evaporator, and the dipyrromethane product was purified over a silica gel column to give 1-(2,3,4,5,6-pentafluoro-1,1,-(2-pyrryl)methane (6.16 g, 97%). The dipyrromethane (99 μL, 0.8 mmol) thus obtained and 2,3,4,5,6-pentafluoro-benzaldehyde (250 mg, 0.8 mmol) were dissolved in CH2Cl2 (20 mL) in a 50 mL round-bottom flask under nitrogen atmosphere and was added 20 μL of 2.5M trifluoroborane etherate (BF3OEt2). After 2 hours, DDQ (280 mg) was added and the solution was stirred for one day. The solvent was removed using a rotary evaporator and the expanded porphyrin products were separated by a column chromatography. As shown in FIG. 2, only the expended polyphyrins with even pyrrole subunits were formed and the separation process was facilitated significantly. Yields of the expanded porphyrins are shown in Table 2.

Provenance & Evidence