Ether, benzyl chloromethyl reaction with carbonyl compounds

Hydroxymethylation of carbonyl compounds.3 Alkyl chloromethyl ethers react in the presence of Sml2 (2 equiv.) with ketones in THF to give adducts in 50-80% yield. The reaction with aldehydes is conducted in tetraethylene glycol dimethyl ether, which suppresses pinacol reduction. Hydroxymethylation of carbonyl compounds can be effected by use of benzyl chloromethyl ether followed by hydrogenolysis of the adduct. 

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