The preferred practice of the Collins method is to use a mole ratio of complexing agent to {HEAD ~ Zr} that is similar to the mole ratio of {TAIL ~ organic base} to Zr 
The preferred practice of the Collins method is to use a mole ratio of complexing agent to { HEAD ~ Zr } that is similar to the mole ratio of { TAIL ~ organic base } to Zr
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH