ebpcb u201d in reaction iii it is important that no catalyst be used while the use of a catalyst is typically standard in an ordinary friedel crafts reaction in the case of this reaction the use of a catalyst will cause undesired side reactions production of polymeric material and unwanted isomers mixing and heating the reaction mixture to boiling is also important to help expel hcl byproduct which would act as an undesired catalyst the temperature is desirably 120 to 180 u00b0 c preferably 140 to 160 u00b0 c more preferably 145 to 155 u00b0 c and ideally 150 to 155 u00b0 c it has been found that xylenes are an exemplary reaction medium xylenes will normally undergo friedel crafts reaction but in the modified friedel crafts reaction conditions of this invention the xylenes do not react r bpcb ebpcb is useful in a novel reaction in which it is cyclized as shown in reaction iv in reaction iv r bpcb ebpcb is reacted with a compound of high oxidative potential that is capable of promoting a single electron transfer by u201c high oxidative potential u201d is meant 1 54 electron volts or greater suitable such compounds of high oxidative potential capable of single electron transfer include ce 3 mn 3 compounds an exemplary compound is ch 3 c o o 3.