805324-11-2Relevant academic research and scientific papers
Functionalised dien ligands of the type (ArNHCH2CH 2)2NR [R = Me, (2-C5H4N)CH 2] and their complexes with iron and cobalt halides
Davies, Christopher J.,Hilton, Stephen J.,Solan, Gregory A.,Stannard, Wesley,Fawcett, John
, p. 2017 - 2026 (2005)
The alkylation of (ArHNCH2CH2)2NH with RX [RX = MeI, (2-C5H4N)CH2Cl] under basic conditions gives (ArHNCH2CH2)2NMe (Ar = 2,6-Me2C6H3 L1a, 2,4-Me2C 6H3 L1b) and (ArHNCH2CH2) 2{(2-C5H4N)CH2}N (Ar = 2,4,6-Me 3C6H2 L2a, 2,4-Me2C 6H3 L2b) in moderate yield, respectively. Alternatively, L1a and L1b can be accessed by the arylation (with Ar-Br) of (H 2NCH2CH2)2NMe in the presence of a catalytic quantity of Pd2(dba)3. Treatment of L1 with CoCl2 in n-BuOH gave high-spin [{(ArHNCH2CH 2)2NMe}CoCl2] (Ar = 2,6-Me2C 6H3 1a, 2,4-Me2C6H3 1b) in good yield; no reaction occurred with FeCl2. The molecular structure of 1a reveals a distorted trigonal bipyramidal geometry with the L1a adopting a mer-configuration. Reaction of L2 with MCl2 affords the cobalt and iron complexes, [{ArNHCH2CH2} 2{(2-C5H4N)CH2}NMCl2] (M = Co, Ar = 2,4,6-Me3C6H2 2a, 2,4-Me 2C6H3 2b; M = Fe, Ar = 2,4,6-Me 3C6H2 3a, 2,4-Me2C6H 3 3b); the octahedral frameworks in 2a and 3a are found to be considerably distorted with one of the two M-N(mesityl-substituted) distances noticeably elongated [M-N 2.597(4)-2.795(2) ?]; no such inequivalence is observed in solution at room temperature. On activation with methylaluminoxane, complexes 1a and 1b display some activity for the oligomerisation of ethylene.
