A Modified Low-cost Preparation of Chloromethyl Methyl Ether (MOM-Cl)

Abstract

The versatile reagent chloromethyl methyl ether (MOM-Cl) is synthesized by using inexpensive starting materials in a large scale. A modification of the existing methods reduces material costs by more than 80%.

Key words

protecting group - MOM-Cl - alcohols - phenols - acetals

References

• 1 Greene TW. Wuts PGM. Protective Groups in Organic Synthesis   3rd ed:  John Wiley and Sons; Weinheim: 1999. 
• 2a Amato JS. Karady M. Sletzinger M. Weinstock LM. J. Org. Chem.  1994,  59:  6499 
• 2b Linderman RJ. Jaber M. Griedel BD. J. Org. Chem.  1994,  59:  6499 
• 2c Chong JM. Shen L. Synth. Commun.  1998,  28:  2801 

3

Material costs are calculated from the prices quoted in the Aldrich Chemical Co. catalog (2003). For comparison, one mole of chloromethyl methyl ether costs 229 US $. A commercial sample of chloromethyl methyl ether contained about 4% of bis(chloromethyl)ether.

4

To ensure gas tightness, PTFE-sleeves were used on all glass connections.

5

All reagents were purchased by common suppliers and used as received without any further purification.

6

The integrals of the product signals (δ = 3.52 and 5.46 ppm) are compared with those of dimethoxymethane (δ = 3.34 and 4.56 ppm).

7

Without further purification, the product contains about 1% dimethoxymethane (¹H NMR, δ = 3.34 and 4.56 ppm). This is sufficient for most applications. The content of bis(chloromethyl)ether was found to be less than 0.1% (GC, conditions 50 m × 0.32 mm FS-SE-52-CB-0.25 fused silica column, column temperature 60 °C, injector temperature 240 °C, detector temperature (FID), nitrogen flow 1 mL/min t_R (MOM-Cl) = 5.79 min, t_R [bis(chloromethyl)ether] = 7.97 min.