Sodium methylsulfinylmethylide

Sodium methylsulfinylmethylide (also called NaDMSO or dimsyl sodium) is the sodium salt of dimethyl sulfoxide. It has the chemical formula CH₃S(O)CH−2Na⁺. This unusual salt has some uses in organic chemistry as a base and nucleophile.

Sodium methylsulfinylmethylide

Names
Preferred IUPAC name Sodium (methanesulfinyl)methanide
Other names sodium dimsylate, dimsylsodium, NaDMSYL
Identifiers
CAS Number	15590-23-5 Y
3D model (JSmol)	Interactive image
Abbreviations	NaDMSO
ChemSpider	8329518 Y
PubChem CID	10154010
UNII	R6HI470Q52 Y
CompTox Dashboard (EPA)	DTXSID10436194
InChI InChI=1S/C2H5OS.Na/c1-4(2)3;/h1H2,2H3;/q-1;+1 Y Key: CWXOAQXKPAENDI-UHFFFAOYSA-N Y InChI=1S/C2H5OS.Na/c1-4(2)3;/h1H2,2H3;/q-1;+1 Key: CWXOAQXKPAENDI-UHFFFAOYAA Key: CWXOAQXKPAENDI-UHFFFAOYSA-N
SMILES [Na+].O=S([CH2-])C
Properties
Chemical formula	CH3S(O)CH2Na
Molar mass	100.11 g·mol−1
Appearance	White solid, solution in DMSO is green
Solubility in water	decomposes
Solubility	Very soluble in DMSO and many polar organic solvents
Hazards
Occupational safety and health (OHS/OSH):
Main hazards	May form corrosive NaOH, May be explosive in certain circumstances.[1]
Related compounds
Related compounds	Dimethyloxosulfonium methylide, Dimethyl sulfoxide
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). N verify (what is YN ?) Infobox references

Since the first publication in 1965 by Corey et al.,^[2] a number of additional uses for this reagent have been identified.^[3]

Preparation

Sodium methylsulfinylmethylide is prepared by heating sodium hydride^[4] or sodium amide^[5] in DMSO^[6]

CH₃S(O)CH₃ + NaH → CH₃S(O)CH−2Na⁺ + H₂

CH₃S(O)CH₃ + NaNH₂ → CH₃S(O)CH−2Na⁺ + NH₃

Reactions

As a base

The pK_a of DMSO is 35, which leads NaDMSO to be a powerful Brønsted base. NaDMSO is used in the generation of phosphorus and sulfur ylides.^[7] NaDMSO in DMSO is especially convenient in the generation of dimethyloxosulfonium methylide and dimethylsulfonium methylide.^[2][8]

Reaction with esters

NaDMSO condenses with esters (1) to form β-ketosulfoxides (2), which can be useful intermediates.^[9] Reduction of β-ketosulfoxides with aluminium amalgam gives methyl ketones (3).^[10] Reaction with alkyl halides followed by elimination gives α,β-unsaturated ketones (4). β-ketosulfoxides can also be used in the Pummerer rearrangement to introduce nucleophiles alpha to a carbonyl (5).^[11]