Please do not adjust margins
Dalton Transactions
Page 6 of 9
DOI: 10.1039/C6DT04896J
ARTICLE
Journal Name
position as in the spectra of the salts with unsubstituted titanyl
Titanium (IV) 2,3-naphthalocyanine dichloride, TiIVCl2(Nc2−).
2,3-Dicyanonaphthalene (1 g, 5.612 mmol),
phthalocyanine radical anions, {O=TiIV(Pc• −)}•−. Partial disruption of
2-
3
aromaticity is observed at the reduction of the macrocycles. This methylnaphthalene (200 mg, 1.403 mmol) and TiCl4⋅2THF (468 mg,
effect is more pronounced for the dianions than for the radical 1.403 mmol) in 10 ml of 1-chloronaphthalene were heated up to
anions. Increased size of the macrocycle leads to the formation of 250 °C upon stirring for 5 hours in argon atmosphere. Then the
π-stacked structures. In case of 2 that provides effective magnetic reaction mixture was cooled down to 50 °C and precipitate was
3
coupling between the spins within the [{O=TiIV(Nc• −)}•−]2 dimers filtered under reduced pressure and washed with toluene and
and the transition of the dimers to the singlet ground state even methanol. TiIVCl2Nc was dried at 100 °C in vacuum for 2 hours to
below 200
K (at temperature higher than that in the yield 850 mg of dark green powder (73%). Anal. found: C, 69.01, N
[{O=TiIV(Pc• −)}•−]2 dimers). Macrocycles in 1 and 3 are packed in the 13.30, H 3.06, Cl 8.44 %. Calcd. for C48H24N8Cl2Ti: C, 69.26, N 13.47,
π-stacked chains. However, diamagnetic nature of the dianions H 2.89, Cl 8.54 %. IR (KBr), ν, cm-1: 1747w, 1639m, 1468w, 1358m,
does not allow one to expect the realization of conductivity or 1338m, 1318m, 1153w, 1125m, 1062s, 1011m, 1077s, 968m, 886m,
magnetic interactions in these chains. We suppose that the radical 863m, 798w, 752s, 733w, 716m, 690w, 656w, 514w, 488w, 469m.
anions of these titanyl macrocycles can provide more promising UV-VIS, KBr pellet λmax, nm: 340, 753, 834.
3
magnetic properties. Preparation of these salts is now in progress.
Acenaphtho[1,2-b]pyrazine-8,9-dicarbonitrile.
mixture of acenaphthenequinone (2 g, 11 mmol) and
A
equimolar quantity of diaminomaleonitrile (1.187 g, 11 mmol) in 30
ml acetic acid was heated at 100 °C upon stirring for 1 hours. The
residue was filtered off, washed with water and acetone (3 ml) and
dried at 100 °C in vacuum for 2 hours to yield 2.15 g of dark orange
powder (77%).
Experimental
Materials
4,5-Dichlorophthalonitrile (Aldrich, 99%), 2,3-dicyanonaphthalene
(TCI,
99%),
acenaphthenequinone
(Acros,
95%),
and
Titanyl tetra(acenaphthenopyrazino)porphyrazine,
O=TiIV(AceTPrzPz2−).
diaminomaleonitrile (Acros, 98%) were used as received. TiCl4
(Aldrich, 99%) and TiCl4⋅2THF (Aldrich, 97%) were used as received.
Bis(triphenylphosphoranylidene)ammonium chloride (PPNCl) was
purchased from Aldrich (98%). 1-chloronaphthalene (Aldrich,
technical grade) was used as received. Sodium fluorenone ketyl was
obtained as described.37 Solvents were purified in argon
atmosphere. o-Dichlorobenzene (C6H4Cl2) was distilled over CaH2
under reduced pressure; hexane was distilled over
Na/benzophenone, and benzonitrile (C6H5CN) was distilled over Na
under reduced pressure. The solvents were degassed and stored in
a glove box. The crystals of 1 – 3 were stored in a glove box. KBr
pellets for IR- and UV-visible-NIR measurements were also prepared
in the glove box. EPR measurements were performed on
polycrystalline samples of 1-3 sealed in 2 mm quarz tubes under 10-
5 Torr.
Acenaphtho[1,2-b]pyrazine-8,9-dicarbonitrile (1 g, 3.933 mmol),
2-methylnaphthalene (140 mg, 0.983 mmol) and TiCl4 (0.11 mL,
0.983 mmol) in 10 ml of 1-chloronaphthalene were heated up to
250 °C upon stirring for 5 hours in argon atmosphere. Then the
reaction mixture was cooled down to 50 °C, precipitate was filtered
under reduced pressure and washed with toluene and methanol.
TiIVCl2(AceTPrzPz2−) was converted to O=TiIV(AceTPrzPz2−) by boiling
in wet pyridine (5% of H2O) for two hours. O=TiIV(AceTPrzPz2−) was
filtered, washed with water and dried at 100 °C in vacuum for 2
hours to yield 800 mg of black powder (75%). Anal. found: C 70.88,
N 20.59, H 2.49 %. Calcd. for C64H24N16OTi: C 71.04, N 20.72, H 2.22
%. IR (KBr), ν, cm-1: 2921m, 2851m, 1615s, 1514m, 1458m, 1431s,
1369w, 1333s, 1262m, 1229s, 1179m, 1134s, 1099m, 1033s, 974w,
947m, 927m, 828m, 772s, 716m, 675m, 660m, 630m, 559w, 464s,
449m. UV-VIS, KBr pellet λmax, nm: 331, 652, 710.
Synthesis of titanyl macrocycles
Titanyl macrocycles (Scheme 2) were synthesized as described in
ref.33
Syntheses of crystalline salts 1-3
Crystals of 1-3 were obtained by diffusion technique. The reaction
solutions of salts 1-3 were filtered in a 50 mL glass tube of 1.8 cm
diameter with a ground glass plug, and 30 mL of hexane was layered
over the solution. Slow mixing of two solvents during 1.5 months
provided precipitation of crystals on the walls of the tube. The
solvent was decanted from the crystals and they were washed with
hexane.
Salts (PPN)2{O=TiIVPcCl8} (1) and (PPN){O=TiIVNc}⋅2C6H4Cl2 (2)
were obtained by reduction of 34.6 mg of TiIVOPcCl8 (0.042 mmol)
or 35.5 mg of TiIVCl2Nc (0.042 mmol) by sodium fluorenone ketyl (55
mg, 0.27 mmol) in the presence of PPNCl (75 mg, 0.131 mmol) in 16
ml of o-dichlorobenzene for two hours at 100oC till complete
dissolution of starting compounds and the formation of dark green
and deep-blue-green solutions, respectively. The final solutions
were filtered into a tube for diffusion. Black blocks of 1 and dark
violet elongated prisms of 2 were obtained in 25 and 45% yield,
respectively.
Titanyl
2,3,9,10,16,17,23,24-octachlorophthalocyanine,
2
O=TiIV(PcCl8 −).
4,5-Dichlorophthalonitrile
(1
g,
5.076
mmol),
2-
methylnaphthalene (180 mg, 1.269 mmol) and TiCl4 (0.14 ml, 1.269
mmol) in 10 ml of 1-chloronaphthalene were heated up to 250 °C
upon stirring for 5 hours in argon atmosphere. Then the reaction
mixture was cooled down to 50°C, precipitate was filtered under
reduced pressure and washed with toluene and methanol.
2
2
TiIVCl2(PcCl8 −) was converted to O=TiIV(PcCl8 −) by boiling in wet
pyridine (5% of H2O) for two hours. O=TiIV(PcCl8 −) was filtered,
2
washed with water and dried at 100 °C in vacuum for 2 hours to
yield 800 mg of blue powder (68%). Anal. found: C, 44.86, N 13.01,
H 1.12, Cl 33.21 %. Calcd. for C32H8N8Cl8OTi: C, 45.08, N 13.15, H
0.94, Cl 33.34 %. IR (KBr), ν, cm-1: 3087m, 2922m, 2849w, 2353w,
1603m, 1471m, 1413s, 1375m, 1320m, 1069s, 980w, 945m, 890m,
829m, 775m, 705m, 659m, 463w, 431w. UV-VIS, KBr pellet λmax
,
nm: 353, 660, 706.
6 | J. Name., 2012, 00, 1-3
This journal is © The Royal Society of Chemistry 20xx
Please do not adjust margins
Faraonov, Maxim A.
