Abstract From the reaction between W 2 (NMe 2) 6 and dimesitylborinic acid,(Mes) 2 BOH (2 equiv.), in toluene, the golden-yellow crystalline compound W 2 (NMe 2) 4 [OB (Mes) 2] 2 (1) has been isolated and characterized (elemental analysis, 1 H, 13 C {1 H}, 11 B NMR spectroscopy, IR spectroscopy and a single crystal X-ray diffraction study). At− 160 C, a= 39.379 (7), b= 13.649 (2), c= 21.918 (4) Å, β= 123.12 (1), Z= 8 and space group C2/c. The ...