摘要:
Re[C(O)Ar'](CO)5 (Ar' = 2,4,6-C6H2Me3; 1) can be prepared in 55% yield by adding ArC(O)Cl to [Re(CO)5]-. Addition of trifluoromethanesulfonic anhydride to 1 in dichloromethane yields off-white [Re(CAr')(CO)4(OTf)](OTf) (2) quantitatively. Three equivalents of tetraethylammonium chloride reacts with 2 in dichloromethane to give [Et4N[Re(CAr)(CO)2Cl3] (3), which when treated with TlBF4 in the presence of pyridine affords lemon yellow Re(CAr')(CO)2Cl2(py)(4). A slurry of 2 in dichloromethane also reacts cleanly with a THF solution of LiO-2,6-C6H3-i-Pr2 (LiOAr) to yield blood red Re(CAr')(CO)2(OAr)2(THF) (5a) in 80% isolated yield. Addition of pyridine to 5a yields an analogous six-coordinate pyridine adduct (5b). Addition of pinacol to 2 followed by triethylamine yields yellow, pentane-soluble Re(CAr')(CO)2(O2C2Me4) (6a). Although 6a shows no tendency to bind THF, it reacts with pyridine to yield Re(CAr')(CO)2(O2C2Me4)(py) (6b) quantitatively. Addition of triphenylphosphine to 6a produces dark red Re(CAr')(CO)(O2C2Me4)(PPh3) (6c).