Synthetic cocaine per so, is a fucktard to synthesize, the reagents needed are somewhat advanced and hard to source, and the synthesis itself is very involved.
Could you be referring to tropacocaine? it's produced by a few simple steps starting from atropine, and ending with esterification with benzoic acid to produce the finished product.
It is supposed to have round about -10x the potency of cocaine, but possibly the ease of synthesis would make it a valid alternative for self use.
Doing the esterification with one of the 4-halogenated benzoic acids, 4-fluorobenzoic acid in particular was reputed to give an increased potency, wether over tropacocaine, or cocaine itself though I am unclear.
I was pretty intrigued about this procedure, it seems some people over at "the other place" just saw the weakened potency and the thread unfortunately drifted into obscurity.
My only problem has been in finding a source of atropine, and SWIM, my friend is looking at chinese herbalists for dried belladonna
I would be interested as to know if 4-chlorotropacocaine also produced the increase in potency, as an intake, especially a regular intake, such as an addict may develop, of a fluorinated compound surely wouldnt prove too healthy8(