2206-27-1,Dimethyl sulfoxide-d6

Physical Properties

• Appearance & Form: Colorless, transparent, and clear liquid with a slight characteristic odor (similar to regular dimethyl sulfoxide).

• Melting & Boiling Points: Melting point is approximately 20.2 °C (slightly higher than regular DMSO's 18.5 °C; tends to freeze/solidify at cooler room temperatures); boiling point is approximately 189 °C.

• Density: Approximately 1.19 g/mL (at 25 °C). Due to deuterium's higher atomic mass compared to hydrogen, its density is significantly higher than that of regular DMSO (1.10 g/mL).

• Hygroscopicity: Extremely hygroscopic. Rapidly absorbs ambient moisture when exposed to air, leading to a marked increase in the water peak ( $H_2O/HDO$ within the solvent signal).

Chemical Properties & Main Uses

• NMR Spectroscopy Solvent (Core Application):

  • Deuterium Lock: As the most commonly used solvent in $^1\text{H-NMR}$, the deuterium atoms in the molecule provide a stable lock signal.

  • Elimination of Solvent Signal Interference: Full deuteration eliminates strong proton interference from the solvent. Extremely minor traces of residual undeuterated protons appear as a characteristic quintet at $\delta = 2.50\text{ ppm}$ (residual solvent peak); absorbed water typically appears near $\delta = 3.33\text{ ppm}$.

• Physicochemical Analysis of Poorly Soluble Compounds: Due to its superior dissolving capacity, it is widely used for the spectral characterization of highly polar, high-molecular-weight, or easily aggregated drug molecules, natural products, and organic intermediates.

• Reaction Mechanism & Kinetics Studies: Serves as a deuterium labeling reagent or reaction medium in organic chemistry to study kinetic isotope effects (KIE) or trace reaction pathways.