Bis(2,2,6,6‐tetramethyl‐3,5‐heptanedionato)nickel(II)

image [ 41749‐92‐2 ] or [ 14481‐08‐4 ] C 22 H 38 O 4 Ni (MW 425.23) InChI = 1S/2C11H20O2.Ni/c2*1‐10(2,3)8(12)7‐9(13)11(4,5)6;/h2*7,12H,1‐6H3;/q;;+2/p‐2/b2*8‐7‐ InChiKey = PIIJAZNTPALBJL‐ATMONBRVSA‐L (used as catalyst for polymerizations, oxidations, hydrofunctionalizations, amide alcoholysis, and cross‐coupling reactions) Alternative Names : nickel(II) bis(2,2,6,6‐tetramethyl‐3,5‐heptanedionate), Ni(TMHD) 2 , Ni(thd) 2 , Nickel(II) di(pivaloyl)methane, Ni(dpm) 2 . Physical Data : mp 219–225 °C. 1–3 bp (sublimation) 90–110 °C/0.1 mm Hg. 3 Solubility : soluble in hexanes, toluene, dichloromethane, ethyl acetate, THF, and DMA; partially soluble in DMSO; insoluble in water. Form Supplied in : dark purple to light purple solid from commercial supplier (Strem catalog number 28‐0088). Recrystallized sample reported to be red needles; dry pink powder reported to turn blue on standing due to hydration. 1 Ni(TMHD) 2 · x H 2 O reported to be a green powder. 4 Analysis of Reagent Purity : elemental analysis. 1 1 H NMR. 5 Preparative Methods : mixing of methanolic solutions of 2,2,6,6‐tetramethylheptanedione and nickel(II) acetate tetrahydrate followed by the addition of water affords a precipitated solid which can be collected and dried. 1 Ultrasonic mixing of a solution of nickel(II) chloride hexahydrate and 2,2,6,6‐tetramethylheptanedione in methanol followed by pH adjustment affords a precipitated solid. 5 This material can also be purchased from commercial suppliers. Purification : recrystallization from hot dichloroethane. 1 Handling, Storage, and Precautions : material can be handled under air with standard personal protective equipment. Dried samples will slowly hydrate on standing under ambient atmosphere. 1 Purified, dried samples should be stored under inert atmosphere in a glovebox or sealed in a desiccator and need only be used in a glovebox if hydration is to be avoided.