C–H Activation by a Diselenido Dinickel(II) Complex

Abstract

Addition of selenium to the nickel(I) complex, [Ni(Me4[12]aneN4)(CO)]PF6, effects a redox reaction leading to the diselenido dinickel(II) complex, {[(Ni(Me4[12]aneN4)]2(Se2)}(PF6)2, in 70% crystalline yield. The product's structure features a μ-η(2):η(2)-Se2 ligand with Se-Se bond length of 2.379(13) Å. Upon mild heating, {[(Ni(Me4[12]aneN4)]2(μ-η(2):η(2)-Se2)}(PF6)2 oxidizes 9,10-dihydroanthracene or 1,4-cyclohexadiene forming the terminal hydroselenide, [Ni(Me4[12]aneN4)(SeH)]PF6, and anthracene or benzene, respectively. [Ni(Me4[12]aneN4)(SeH)]PF6 cleanly converts back to the diselenido dinickel(II) adduct upon addition of a phenoxy radical.

Mechanistic Insight into H/D Exchange by a Pentanuclear Ni–H Cluster and Synthesis and Characterization of Structural Analogues of Potential Intermediates

“…In both cases, 1 was not immediatly consumed, but acted as a hydrogen-transfer catalyst, forming equivalent amounts of benzene and cyclohexene immediately at room temperature. Similar reactivity with nickel complexes has been reported . Over the course of an hour, the cyclohexene produced reacted with 1 , forming multiple products that included the known carbide cluster, [( i Pr 3 P)­Ni] 5 H 4 (μ 5 -C), from CC bond cleavage.…”

“…Similar reactivity with nickel complexes has been reported. 75 Over the course of an hour, the cyclohexene produced reacted with 1, forming multiple products that included the known carbide cluster, [( i Pr 3 P)Ni] 5 H 4 (μ 5 -C), from CC bond cleavage. In an attempt to avoid the thermodynamic driving force provided by aromatization in these reactions, 1,4-pentadiene was reacted with 1 in an attempt to make the acyclic analogue (η 5 -C 5 H 7 )Ni[( i Pr 3 P)Ni] 4 (μ 2 -H) 4 (μ 5 -H).…”

Dihydrobis(methimazolyl)borato complexes of ruthenium and osmium

“…Rauchfuss has, however, spectroscopically characterised the complexes [Ru(SeH)(PPh3)2{h-C5H4R) (R = H, Me, Et). 29 Useful structural data for mononuclear terminal hydroselenido complexes in general are somewhat sparse, [30][31][32][33][34][35] and when the SeH hydrogen position is (rarely) located, the M-Se-H angle is close to 90° consistent with negligible (i.e., "p 3 ") hybridisation. In the present case, this angle is obtuse (136(1)°) however its proximity to both ruthenium and selenium render this metric imprecise.…”

Reactivity of uranium(iii) with H2E (E = S, Se, Te): synthesis of a series of mononuclear and dinuclear uranium(iv) hydrochalcogenido complexes

“…IR spectroscopy can be a useful tool to determine the presence of an EH group, since the characteristic, but oen rather weak IR-active n (E-H) bands usually appear in the regions between 2300-2600 cm À1 (SH), [70][71][72][73][74][75][76] 2200-2500 cm À1 (SeH), [74][75][76][77][78][79][80][81][82] and 1800-2000 cm À1 (TeH). 74,76,83 However, complexes 1-SH and 2-SH, as well as 1-SeH, 1-SeD and 2-SeH, do not show any n (E-H) bands at all, a fact that was also observed in several transition metal complexes.…”