N -Methyl-2-pyrrolidone (NMP)

N-Methyl-2-Pyrrolidone (NMP), with the CAS Number 872-50-4, is a lactam reagent used in peptide synthesis for washing, deprotection, and splitting purposes. It has a Molecular Weight of 99.13 g/mol. In the workplace, it is classified as a substance that may cause substantial skin contamination and requires specific precautions such as no smoking, no unauthorized access, no eating or drinking, and use of safety equipment like goggles and gloves. The European Union has set binding occupational exposure limits for NMP, with an 8-hour limit value of 40 mg/m3 (10 ppm) and a short-term limit value of 80 mg/m3 (20 ppm).

• CAS Number: 872-50-4
• Molecular Formula: C5H9NO
• Molecular Weight: 99.13
• Exact Mass: 99.068413911
• Boiling Point: 396 °F at 760 mmHg (NTP, 1992)
• Melting Point: -9 °F (NTP, 1992)
• Vapour Density: 3.4 (NTP, 1992) - Heavier than air; will sink (Relative to Air)
• GHS Signal Word: Danger
• Hazard Statements:
• H315: Causes skin irritation [Warning Skin corrosion/irritation]
• H227: Combustible liquid [Warning Flammable liquids]