Bis (ary1oxy) dichloromethanes (eg 1) are readily available by radical-induced chlorination of formaldehyde diary1 acetals'). Like 2, 2-dichloro-1, 3-benzodioxol, which is used for the electrophilic carboxylation of aromatic compounds*) and of alkenes3), they represent R02C@ equivalents and have been employed for the synthesis of P, y-unsaturated esters from allyl~ ilanes~). In this paper we report on the reaction of bis (ary1oxy) ...