An excess of a tertiary amine, e.g. diisopropylethylamine, N methylmorpholine, N methylpyrrolidine or {HEAD ~ 4 DMAP} is added to maintain the reaction mixture at {TAIL ~ a pH} of about 8 
An excess of a tertiary amine , e.g. diisopropylethylamine , N methylmorpholine , N methylpyrrolidine or { HEAD ~ 4 DMAP } is added to maintain the reaction mixture at { TAIL ~ a pH } of about 8
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH