By a neutral Lewis acid is meant {HEAD ~ a compound} which is {TAIL ~ a Lewis acid} capable for abstracting X from to form a weakly coordinating anion 
is
By a neutral Lewis acid is meant { HEAD ~ a compound } which is { TAIL ~ a Lewis acid } capable for abstracting X from to form a weakly coordinating anion
OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH