Stereoelectronic Characterization and Catalytic Potential of a 1,3‐Bis(2,6‐terphenyl)‐Substituted N‐Heterocyclic Carbene

Abstract

The preparation of a 1,3-bis(2,6-terphenyl)imidazol-2-ylidene, IDitop (Ditop = 2,6-bis(4-tolyl)phenyl-) is reported. Several late transition metal complexes as well as the selenium adduct of IDitop were prepared to study and compare the stereoelectronic properties of IDitop to other well-known N-heterocyclic carbenes (NHCs). A study of the steric character of IDitop taken from crystal structure data of the complexes and adducts reveals a high degree of flexibility. Preliminary application to challenging Suzuki coupling reactions was undertaken.

Catalytic exploration of NHC–Ag(i)HMDS complexes for the hydroboration and hydrosilylation of carbonyl compounds

“…Interestingly, the G value for 3 , our most active pre-catalyst, is the largest at G M 43.9, which could indicate that the bulk of IDipp lies on the frontier of the Ag( i ) coordination sphere, which was not captured relying on % V Bur alone to quantify steric hinderance and/or bulk. 50,51 In comparison, complex 5 showed little variance in steric contribution across the calculated % V Bur and G M parameter values (Table 4).…”