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10th February 2013 @ 23:32

H1 NMR data showed starting material reacting in an unwanted way with the thionyl chloride. It was decided to redo experiment and try to isolate the product and to investigate other chlorinating agents.

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Investigation of sulfonamide synthesis via NMR.

 

Reaction time: 7:00 PM EST, 10/2/13

MD 6-5 (20 mg, 0.068 mmol, 1 equiv.) was stirred in d-DMSO (1.5 mL) NMR1 taken. Thionyl chloride (20 µL, 0.068 mmol, 1 equiv.) was added, followed by NMR2 and the reaction was left overnight. In the morning3 further thionyl chloride (20 µL) was added and NMR4 was taken. Starting material seemed to be reacting in an unwanted way with the thionyl chloride. It was decided to redo experiment and try to isolate the product.

NMR Data:

DMSO1.pdf
: Spectrum of MD 6-5 in d-DMSO.

DMSO2.pdf
: Spectrum after addition of 1 equivalent of SOCl2. Peaks at δ 2.08 and δ 2.06 may be due to sulfonation on the pyrrole.

DMSO3.pdf
: No change after 16 hours at room temperature.

DMSO4.pdf
: Addition of another 1 equivalent of SOCl2 causes the peaks at δ 6.0, δ 2.04 and δ 1.86 to disappear indicating absence of starting material.

See also: Synthesis of sodium 1-(4-fluorophenyl)-2,5-dimethyl-1H-pyrrole-3-sulfonate (MD 6-5)

Synthesis of N-benzyl-1-(4-fluorophenyl)-2,5-dimethyl-1H-pyrrole-3-sulfonamide (MD 12-4)

Risk and hazard assessment: Same as Synthesis of N-benzyl-1-(4-fluorophenyl)-2,5-dimethyl-1H-pyrrole-3-sulfonamide (MD 12-2)

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Attached Files
DMSO1.pdf
DMSO2.pdf
DMSO4.pdf
DMSO3.pdf