Recently, subphthalocyanines, the "little sisters/brothers" of the well-known phthalocyanines
have attracted considerable interest among material and synthetic chemists.
Subphthalocyanines, as well as
phthalocyanines and the superphthalocyanines (in terms of family: the "bigger sisters/brothers"), belong to
the family of circular polyisoindolenines, in which the isoindole units are linked by azamethine groups.
These materials are now actively under investigation for their role as starting materials
for the synthesis of unsymmetrically substituted phthalocyanines, or as materials with particularly
high non-linear optical sensitivity in second-harmonic or third-harmonic generation. We were
interested in the arrangement behavior of non-planar aromatic macrocycles in single-crystals or thin films.
We synthesized several subphthalocyanine compounds SubpcB-X (with X= phenyl, OMe, OSi(tBu)Me2)
and could separate them from brominated by-products by extensive crystallization and/or chromatography.
A by-product from the synthesis of the phenyl-substituted subphthalocyanine has been identified
by single-crystal analysis as a boron-substituted beta-isoindigo complex. We could obtain single-crystal
structures from all our compounds, from the methoxy-substituted compound even two different ones.
An overview of our results is given in our publication:
Chem.Abstr: 130:39766 (1999)
Synthesis, Structural Characterization and Optical Properties of Several Boron Subphthalocyanines and a Boron beta-Isoindigo Complex.
Michael K. Engel, J. Yao, H. Maki, H. Takeuchi, H. Yonehara, C. Pac, Kawamura Rikagaku Kenkyusho Hokoku (1997), 1998, 53-65 (English)
pdf file (8 MB)
In addition to publishing our own work, this paper was the first review on the crystal chemistry of subphthalocyanines.
P. 54, Figure 1b, the nitrogens of the aza-bridges of the subphthalocyanine are missing
p.63, second column, 9th line from the end: reference 6 should read reference 4
p. 64, chapter 4.2, line 3, refs 18,19 should read refs 17,18
p. 64, chapter 4.2, line 9, ref 19 should read ref 18
If you find additional mistakes, please let me know.
The structures are available as CIF files from the Cambridge Crystallographic Data Centre (data request).
In this paper, I make reference (ref 26) to my review about single-crystal structures of
phthalocyanines, you can find it on-line too (pcrev.htm).
Other references to reports from Kawamura Institute of Chemical Research can be obtained
Structural Chemistry of Phthalocyanine Complexes
CELL a 11.558(3) b 15.834(2) c 12.099(2) beta 110.15(1) z 4 sg P21/n cent 1
FORMUL C25 H15 B1 N6 O1
POLYMORPH: monoclinic polymorph
CELL a 12.317(3) b 15.279(2) c 10.5637(8) z 4 sg Pnma cent 1
FORMUL C25 H15 B1 N6 O1
POLYMORPH: orthorhombic polymorph
CELL a 12.639(4) b 12.302(6) c 18.048(2) beta 100.27(2) z 4 sg P21/a cent 1
FORMUL C30 H27 B1 N6 O1 Si1
CELL a 17.475(9) b 18.32(1) c 14.366(9) z 8 sg Pbca cent 1
FORMUL C30 H17 B1 N6
CELL a 35.649 b 9.616 c 18.791 beta 96.12 z 8 sg C2/c cent 1
FORMUL C40 H28 B1 N2
boron beta-isoindigo derivative
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