The reaction of $(CO_5$)M=C(OMe)Tol (M=Cr, Mo, W and $Tol=p-C_6H_4Me)$ and $BBr_3$ followed by treatment with tetramethylethylenediamine (TMEDA) yields a mixture of two diastereomers, trans, $cis-Br(CO)_2(tmeda)M{equiv}$CTol [M=Cr(1a), Mo(2a), W(3a)] and cis, $trans-Br(CO)_2(tmeda)M{equiv}$CTol [M=Cr(1b), Mo(2b), W(3b)], respectively. These compounds have been isolated as crystalline solids and characterized by spectroscopic (infrared, mass, $^1H$ and $^{13}C-NMR)$ data. The trans, cis-Br(CO)2(tmeda)Cr${equiv}$CTol (1a), has been examine via a single crystal X-ray diffraction study : $BrCrO_2N_2C_{16}H_{23}$, Mr=407.27, triclinic, $P{ar{1}},;a=12.792(2),;b=13.400(5),;c= 11.645(4);{AA},;{alpha}=101.26(2)^{circ},;{eta}=103.04(2)^{circ},;{gamma}=91.88(2)^{circ},;{ u}=1907(1){AA}^3,;Z=2,;{ ho}(calcd)=1.418;gcm^{-3},;{lambda}(MoK{alpha})=0.71069;{AA},;{mu}=26.25 cm^{-1},;F(000)=831.97,;T=295K,;R=0.0977$ for 1332 significant reflections $[F_0>5{sigma}(F_0)]$. There are two essentially equivalent molecules in the crystallographic asymmetric unit. Each molecule is octahedral with the bromide ligand trans to the alkylidyne carbon, the two cis-carbonyl ligands, and the bidentate TMEDA ligand.