The mixture is stirred for from 6 to 24 hours at {TAIL ~ room temperature} to complete {HEAD ~ the reaction} 
The mixture is stirred for from 6 to 24 hours at { TAIL ~ room temperature } to complete { HEAD ~ the reaction }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD