Calcium hydride acyl halides

The hydride is an excellent reagent for drying bydrocaibons, ethers (inclwling dioxane and tetrahydroftirane), amines (including pyridine), esters, the butanols (but not methanol or ethanol, which form alkoxides). Since the hydride is an effective condensation catalyst, it should not be used to dry aldriiydes, reactive ketones, acids, or acyl halides. Chlorides and bromides should be dried over calcium hydride only at moderate temperatures. 

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