The reaction is conveniently carried out in an inert organic solvent in the presence of a catalytic amount of an organic or inorganic acid such as {HEAD ~ p toluenesulphonic acid} or {TAIL ~ dry hydrochloric acid} 
The reaction is conveniently carried out in an inert organic solvent in the presence of a catalytic amount of an organic or inorganic acid such as { HEAD ~ p toluenesulphonic acid } or { TAIL ~ dry hydrochloric acid }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL