CB_7~- :Experimental and Theoretical Evidence against Hypercoordinate Planar Carbon

摘要

In organic chemistry,saturated carbon is known to bond to four ligands tetrahedrally,as first recognized independently by J.H.van't Hoff and J.A.Le Bel in 1874.However,after the proposal by Hoffmann and co-workers of tetracoordinate planar carbon in 1970,extensive experimental and theoretical efforts were made to search for so-called anti-van't Hoff/anti-Le Bel molecules (for recent reviews,see references [2-4]).