Azobisisobutyronitrile → 4-(Bromomethyl)-1-fluoro-2-phenoxybenzene

Participants

Reaction Steps

For example, 4-fluoro-3-phenoxy-toluene, when reacted with N-bromosuccinimide in the presence of a radical initiator, for example azodiisobutyronitrile, optionally using a diluent, for example carbon tetrachloride, optionally using a diluent, and 100° C., gives 4-fluoro-3-phenoxy-benzyl bromide. From this, 4-fluoro-3-phenoxy-benzaldehyde can be prepared in a Sommelet reaction, that is to say by reaction with hexamethylenetetramine in the presence of a diluent, for example methylene chloride, at temperatures between 0° and 50° C., followed by reaction with aqueous acetic acid and thereafter with hydrochloric acid, at temperatures between 80° and 120° C. The reaction of 4-fluoro-3-phenoxy-benzaldehyde with sodium cyanide in aqueous acetic acid at 20° C. gives α-cyano-4-fluoro-3-phenoxy-benzyl alcohol. The reaction sequence described above is outlined in the following equations: ##STR11##

Provenance & Evidence