M-Butyl ether

This preparation is an example of the use of di-M-butyl ether as a solvent in the Grignard reaction. The advantages are it is comparatively inexpensive, it can be handled without excessive loss due to evaporation, simple distillation gives an ether free from moisture and alcohol, and the vapour does not form explosive mixtures with air. n-Butyl ether cannot, of course, be employed when the boiling point of the neutral reaction product is close to 140°. 

The traditional method for preparing (m-butyl ethers involves reacting a large excess of isobutene with a solution of the alcohol in dichloromethane in the presence of concentrated sulfuric acid, p-toluenesulfonic acid or phosphoric acid and the method is effective for protecting the side chain hydroxyl functions of serine, threonine [Scheme 4.123], and tyrosine.223 224 A more convenient method involving use of Amberlyst H-15 resin in hexane as the acid catalyst deserves wider attention.217... 

The preparation of /m-butyl ethers requires a large excess of isobutene (bp -6.9 °C) and the inconvenience and potential hazard of a pressure vessel or a sealed tube in some cases, ten-Amyl (T m) ethers have the same lability as tert-butyl ethers towards acids, and they are prepared the same way, by reaction of the alcohol with 2-methyl-l-butene (bp 31 °C) in the presence of trifluoroborane etherate, but they require only a slight excess of the reagent [Scheme 4.128].228 Deprotection of rm-butyl and fer/-amyl ethers can be accomplished by treatment with a catalytic amount of TBSOTf. When a stoichiometric... 

In the preparation of ethyl /m-butyl ether, for example, the following combinations are conceivable ... 

About 70 per cent of the M-butyl ether is recovered readily and may be purified by distillation. 

The di-M-butyl ether may be recovered in pure condition by a simple distillation after the water has been separated from it. 

Propylene glycol 2-M-butyl ether 1,2-Propylene glycol dinitrate 1,2-Propylene glycol monomethyl ether 1,2-Propylene glycol monomethyl ether acetate Propyleneimme Propyl formate... 

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