The polyether bridged diphosphines,(n = 1,2) have been prepared in 60-70% yield by reduction of the corresponding diphosphinedioxides with SizCls or (i-Bu)zAIH. These diphosphinedioxides have been prepared in 75-90% yield by reaction of two equivalents of the appropriatewith one equivalent of di-and triethylene glycol ditosylate.In general, reaction between the diphosphines, Rh(COD)acac and HCIO1, gives a mixture of species, cis-[Rh(COD)(P P)] [C104] being the main complex. This complex reacts with CO to q3-transuwCOHP~P)I w41.