This invention relates to {HEAD ~ a Group 8 metal containing catalyst compound} for {TAIL ~ the metathesis} of olefins 
This invention relates to { HEAD ~ a Group 8 metal containing catalyst compound } for { TAIL ~ the metathesis } of olefins
OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH