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