ok trying the random word thing with _Organic Syntheses_ again. the word of the day is "thirsty"
and it matches one article, wow
http://www.orgsyn.org/demo.aspx?prep=CV6P0153
cyclization of 1,3-dihaloalkanes to cyclopropanes by an electrolytic method! (also 1,4-dihaloalkanes yield cyclobutanes but it's not as good)
preparative electrochemistry is always one of those things I kinda look at with a slightly jaundiced eye. you need specialized equipment. and, in this case, a mercury-pool cathode. bleh
oh, and the thirst?
"and the porous Vycor plugs are cut from lengths of 1/8-in.-diameter porous Vycor rod (_thirsty_ glass or Corning Vycor No. 7930), available from the Electronic Parts Department, Corning Glass Works, Houghton Park, Corning, New York, 14830."
so there ya go. glass can be thirsty.
so far as I know you can't really substitute anything for mercury, when you're using it as a liquid electrode. mercury's electrochemical properties are pretty unique to it
what's the alternative anyway? for closing these small rings, Wurtz coupling with sodium metal, usually a crap reaction, is actually good. but the electrolytic procedure probably has more selectivity and control.
I've vaguely heard of, like, activated non-alkali metals being used. or samarium diiodide