Chloromethylation of syn-[2.n]metacyclophanes and application toward multi-bridged cyclophane synthesis

Dimethoxy[2.n]metacyclophanes (n=3–5) gave the pseudo-ipso or pseudo-ortho products of dichlorides by chloromethylation. Dichlorides were converted to furnish multi-bridged cyclophanes by changing the chloromethyl group to a vinyl group.