| Abstract
| - Two phenol-based compartmental ligands of the “end-off” type,2,6-bis{N-[2-(dimethylamino)ethyl]iminomethyl}-4-methylphenol (HL1) and2-{N-[2-(dimethylamino)ethyl]iminomethyl}-6-{N-methyl-N-[2-(dimethylamino)ethyl]aminomethyl}-4-bromophenol (HL2), have been used to form[Ni2(L1)(AcO)(NCS)2(MeOH)](1),[Ni2(L1)(AcO)2(MeOH)]BPh4 (2),[Ni2(L2)(AcO)(NCS)2(MeOH)](3),[Ni2(L2)(AcO)2]BPh4(4), and[Ni2(L2)(NCS)3(MeOH)](5). X-ray crystallographic studies were done for2−5. 2: triclinic, spacegroup P1̄, a = 13.613(3) Å, b=16.475(4) Å, c = 11.307(4) Å, α =99.90(2)°, β = 104.16(2)°, γ = 109.01(2)°,V = 2253(1) Å3, Z = 2.Thecomplex cation has a dinuclear core triply bridged by the phenolicoxygen of (L1)- and two acetate groups inthesyn-syn mode. One Ni has a six-coordinate geometry together with amethanol oxygen. 3: triclinic, space groupP1̄, a = 10.167(1) Å, b= 16.119(2) Å, c = 9.472(3) Å, α =103.53(2)°, β=100.91(1)°, γ = 85.62(1)°,V =1481(1) Å3, Z = 2. A pair of Niions are bridged by the phenolic oxygen of(L2)-, an isothiocyanatenitrogen,and an acetate group. The sixth position of one Ni is occupied bya methanol oxygen and that of the other Niby isothiocyanate nitrogen. 4: monoclinic, spacegroup P21/n, a =15.146(2) Å, b = 9.442(3) Å, c =30.844(2)Å, β = 93.427(9)°, V = 4402(1)Å3, Z = 4. Two Ni ions are bridged bythe phenolic oxygen of (L2)- andanacetate group. The Ni bound to the iminic pendant arm is nearlyplanar whereas the Ni bound to the aminicpendant arm is of six-coordination together with a bidentate acetategroup. 5: monoclinic, space groupC2/c, a= 26.744(5), b = 10.323(4) Å, c= 21.785(6) Å, β = 94.73(2)°, V = 5993(3)Å3, Z = 8. Two Ni ions arebridged by the phenolic oxygen of (L2)- andan isothiocyanate nitrogen. The Ni bound to the iminicpendantarm is of five-coordination along with an isothiocyanate nitrogen.The Ni bound to the aminic pendant arm hasa six-coordinate geometry together with a methanol oxygen and anisothiocyanate nitrogen. 1−5 wereexaminedregarding their ability to bind urea, and 4 and 5were shown to form[Ni2(L2)(AcO)2(urea)]BPh4(4‘) and [Ni2(L2)(NCS)3(urea)] (5‘),respectively. 5‘ crystallizes in the monoclinic system,space group P21/n, with a= 11.709(5), b = 15.100(4), c = 17.548(5)Å, β = 95.58(3)°, V = 3087(1)Å3, and Z = 4. Its dinuclear core isverysimilar to that of 5 except that the methanol of5 is replaced by a urea molecule.
- 2,6-Bis{N-[2-(dimethylamino)ethyl]iminomethyl}-4-methylphenol(HL1) and2-{N-[2-(dimethylamino)ethyl]iminomethyl}-6-{N-methyl-N-[2-(dimethylamino)ethyl]aminomethyl}-4-bromophenol(HL2) form the dinuclear Ni(II) complexes[Ni2(L1)(AcO)(NCS)2(MeOH)](1),[Ni2(L1)(AcO)2(MeOH)]BPh4(2),[Ni2(L2)(AcO)(NCS)2(MeOH)](3),[Ni2(L2)(AcO)2]BPh4(4), and[Ni2(L2)(NCS)3(MeOH)](5), of which 4 and 5 bind a urea togive[Ni2(L2)(AcO)2(urea)]BPh4(4‘) and[Ni2(L2)(NCS)3(urea)](5‘), respectively.
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