A bidirectional tunnel-like structure with a rigid, thick, and chiral aromatic macrocycle prepared by self-complementary 6,6′-substituted binaphthyl monomer

Article abstract of DOI:10.1246/cl.2008.660

A rigid, thick, and optically active aromatic macrocycle having 6,6′-binaphthylylene moieties was successfully obtained in a moderate yield by synthesis and SNAr of 6-(4-fluorobenzoyl)-6′-hydroxy-2,2′- dimethoxy-1,1′-binaphthyl. The X-ray crystal structural analysis of the obtained macrocycle reveals rigid concavo-concave shape of the molecule and the bidirectional tunnel-like structure assembly consisting of two types of channels along a axis and c axis originated by intra- and intermolecular cavities, respectively. Copyright

Full text of DOI:10.1246/cl.2008.660

660
Chemistry Letters Vol.37, No.6 (2008)
A Bidirectional Tunnel-like Structure with a Rigid, Thick, and Chiral Aromatic Macrocycle
Prepared by Self-complementary 6,60-Substituted Binaphthyl Monomer
Kazuhiro Kumeda,1 Munetosi Ono,1 Atsushi Kawai,1 Hideaki Oike,1 Keiichi Noguchi,2 and Noriyuki Yonezawaꢀ1
1Department of Organic and Polymer Materials Chemistry, Tokyo University of Agriculture & Technology,
2-24-16 Naka-machi, Koganei, Tokyo 184-8588
2Instrumentation Analysis Center, Tokyo University of Agriculture & Technology,
2-24-16 Naka-machi, Koganei, Tokyo 184-8588
(Received March 17, 2008; CL-080287; E-mail: yonezawa@cc.tuat.ac.jp)
A rigid, thick, and optically active aromatic macrocycle
having 6,60-binaphthylylene moieties was successfully obtained
in a moderate yield by synthesis and SNAr of 6-(4-fluorobenzo-
yl)-60-hydroxy-2,20-dimethoxy-1,10-binaphthyl. The X-ray crys-
tal structural analysis of the obtained macrocycle reveals rigid
concavo–concave shape of the molecule and the bidirectional
tunnel-like structure assembly consisting of two types of chan-
nels along a axis and c axis originated by intra- and intermolec-
ular cavities, respectively.
binaphthyl followed by cyclization at the 6,60-positions and the
X-ray crystal structure of the resulting macrocyclic dimer.
To perform this macrocycle synthesis, hydroxy and 4-
fluorobenzoyl groups are the choice of substituents for
unsymmetrically 6,60-functionalized binaphthyl 6. Precursor 6
was obtained by 10 steps in a 30% yield (Scheme 1).5 For
details, see ESI.6 The condensation reaction of precursor 6
yielded binaphthyl dimer 7 as the main product and trimer
8 as a subproduct.7,8 The successful intermolecular cyclodimeri-
zation is probably attributed to the suitable geometry of 4-
fluorobenzoyl and hydroxy groups against intramolecular bond
formation in the open dimeric intermediate formed after the first
nucleophilic aromatic substitution. However, this open dimer
probably has still sufficient width of the groove of the
binaphthylylene moiety to react intermolecularly yielding the
trimer as subproducts and also oligomers as minor ones.
Rigid macrocycle is one of the most fascinating subjects in
recent organic chemistry. For effective synthesis of such rigid
cyclic skeleton, the thermodynamically advantageous macrocy-
clic structure and the choice of the synthetic route employing
the best-fitted precursor for cyclization are essential. Thus, the
design of the ring-closing precursor of depressed perturbation
of conformation is naturally required with fine combination of
several synthetic strategies to prevent uncontrolled oligomeriza-
tion during macrocycle synthesis.1a The utilization of the copla-
narly stretched subunit such as cyclic phenyleneethynylenes has
been reported, which enables to fix the bond-forming functional
groups at the preferable positions for selective ring closing.1
On the other hand, some of the designed rigid planar macro-
cycles have revealed to form unidirectional channels in the as-
sembled solid state.1d In a natural course of this, nonplanar rigid
macrocycles are expected to achieve higher ordered intermolec-
ular stacking. One of the most appropriate candidates for the
starting molecule of this transformation is 1,10-binaphthalene-
2,20-diol (BINOL). BINOL has optically active rigid molecular
skeleton and relatively large cavity. There have been reported
many synthetic studies of BINOL-based macrocyclic com-
pounds with flexible linkers at 2,20-positions.2 However, there
have been reported only a few homologous compounds having
rigid linkers. This is presumed to be due to difficulty of control-
led introduction of rigid and bulky linker units to sterically hin-
dered 2,20-positions. Furthermore, there have been also only a
few reports on the synthesis of the macromolecules by enchain-
ment at the 6,60-positions though the 6,60-positions are situated
at the open edge of the wide cavities in BINOL unit.3
Single crystal of cyclic dimer 7 containing three EtOAc and
one MeOH molecules per each macrocycle was obtained as
yellow cube of the chiral space group C2221.9 The macrocycle
˚
is roughly donut-like shaped with an internal cavity of 4.0 A
HO OH
PivO OH
MeO OMe
c, d, e
a, b
NO2
NH2
1
2
3
f, g
MeO OMe
MeO OMe
MeO OMe
i, j
h
OAc
OH
OH
F
6
5
4
O
k
O
MeO
MeO
OMe
OMe
O
O
O
O
O
MeO
MeO
OMe
OMe
O
O
O
O
8
7
MeO OMe
The authors’ group has reported the selective 6,60-aroylation
reaction of 2,20-dimethoxy-1,10-binaphthyl and the application
to aromatic polyketone synthesis.4 The results prompted the au-
thors to construct macrocyclic compounds by bond formation at
the 6,60-positions leaving the 2,20-oxy group free to be applicable
against another chemical modification. In this paper, the authors
discuss the synthesis of rigid and thick macrocycles utilizing the
unsymmetrical 6,60-functionalization of 2,20-dimethoxy-1,10-
Scheme 1. Synthesis of binaphthyl dimer 7 and trimer 8: (a)
PivCl, Et3N, CH3CN; (b) HNO3 H2SO4, Et2O, 82% (two steps);
.
(c) KOH, H2O, THF; (d) MeI, K2CO3, acetone; (e) SnCl2 2H2O,
EtOH, 72% (three steps); (f) H2SO4, NaNO2, AcOH, H2O; (g)
H2SO4, reflux, 70% (two steps); (h) AcCl, Et3N, CH2Cl2, quant.;
(i) 4-fluorobenzoyl chloride, AlCl3, CH2Cl2; (j) KOH, H2O,
THF, 74% (three steps); (k) K2CO3, DMF, reflux, dimer 7,
40%; trimer 8, 6%.
Copyright Ó 2008 The Chemical Society of Japan

Chemistry Letters Vol.37, No.6 (2008)
661
Figure 1. (Left) ORTEP drawing of cyclic dimer 7 with thermal ellipsoids at the 50% probability level. (Center) View down the a axis
of crystal packing. (Right) View down the c axis. (H atoms and solvent molecules are omitted for clarity.) For details, see ESI.6
˚
[H(24)ꢁꢁꢁH(25a)] by 8.1 A [C(7)ꢁꢁꢁC(7a)]. The dihedral angle be-
tween the phenylene ring and the ether-linked naphthalene ring
is 64.4(1)ꢂ, that between the phenylene ring and carbonyl-linked
naphthalene ring is 86.6(1)ꢂ, and that between the naphthalene
rings is 71.6(1)ꢂ (Figure 1; Left). The phenylene rings are paral-
lel to each other and almost coplanar with the best plane of the
macrocycle, while the two types of naphthalene rings are nearly
perpendicular. The assembled solid structure of macrocycle
7 possesses two different types of channels along the a axis
(Figure 1; Center) and the c axis (Figure 1; Right).
macrocycles and the homologous ones in the selective synthesis
and the expression of structure aiming organic materials having
unique cavity.
This work was financially supported, in part, by SEIKO
PMC CORPORATION.
References and Notes
1
a) W. Zhang, J. S. Moore, Angew. Chem., Int. Ed. 2006, 45, 4416.
b) D. Zhao, J. S. Moore, Chem. Commun. 2003, 807. c) D.
Venkataraman, S. Lee, J. Zhang, J. S. Moore, Nature 1994, 371,
Macrocycle 7 has dual peak-to-trough periphery giving
concavo–concave molecular surface. One face of the molecule
has two salient naphthalene rings linked to carbonyl groups
and the other has the in-plane naphthalene rings linked to
ethereal oxygen. The characteristically shaped molecules should
be locked with the adjacent molecules by two noncovalent
interactions of the phenylene rings and the salient naphthalene
groups with deviation of half a period. Thus, macrocycle 7
is aligned at a tilt in the ab plane with the common direction,
making a thick and monomolecular-layer sheet.
In this sheet, rhombus-arranged unit of unidirectional
macrocycles forms a cavity making the sheet porous. The sheets
having the counter direction of the macrocycle are accumulated
along c axis alternately with superposition of the pores through
the accumulated sheets. Moreover, the sheets have another type
of parallel channels formed by the superposition of the cavity
along the columns of the macrocycles penetrating the monomo-
lecular layer of the sheets parallel to each other and perpendic-
ular to the first channels. Then, a bidirectional tunnel-like struc-
tured organic solid is formed.
Similar bidirectional porosity has been reported by
Tykwinski et al. in the study on the solid structure of the
metal complex of arylene–ethynylene macrocycle (AEM).10
The formation of additional channel was explained as a result
of the conformational change of the AEM to boat-like brought
about by the metal-assisted face-to-face dimerization.
The characteristic solid structure of macrocycle 7 bearing
two types of channels without the aid of metal additives is
presumably attributed to the rigid, thick, and optically active
concavo–concave molecular structure.
591. d) S. Hoger, D. L. Morrison, V. Enkelmann, J. Am. Chem.
¨
Soc. 2002, 124, 6734.
2
a) Y. Hosokawa, T. Kawase, M. Oda, Chem. Commun. 2001, 1948.
b) P. Suresh, S. Srimurugan, H. N. Pati, Chem. Lett. 2007, 36, 1332.
c) G. W. Gokel, W. M. Leevy, M. E. Weber, Chem. Rev. 2004, 104,
2723.
P. P. Castro, F. Diederich, Tetrahedron Lett. 1991, 32, 6277.
A. Okamoto, R. Mitsui, K. Maeyama, H. Saito, H. Oike, Y.
Murakami, N. Yonezawa, React. Funct. Polym. 2007, 67, 1243.
H. Hocke, Y. Uozumi, Tetrahedron 2003, 59, 619.
3
4
5
6
Supporting Information is available electronically on the CSJ-
Journal Web site, http://www.csj.jp/journals/chem-lett/index.html.
Typical procedure for the nucleophilic aromatic substitution cycli-
zation is described in the followings: A solution of 6-(4-fluoro-
benzoyl)-60-hydroxy-2,20-dimethoxy-1,10-binaphthyl (6, 0.2 mmol)
in 20 mL of DMF was added K2CO3 (0.3 mmol) and stirred in
refluxing for 24 h. The mixture was poured into water (40 mL) and
extracted with EtOAc. The organic layer was washed with brine
and dried over MgSO4. After removal of the solvent in vacuo, the
reaction mixture was separated by PTLC (CHCl3) to afford dimer
7 (40%) and timer 8 (6%).
Dimer 7: 1H NMR (300 MHz, CDCl3): ꢀ 3.76 (3H, s), 3.85 (3H, s),
6.91 (1H, d, J ¼ 9 Hz), 6.96 (1H, d, J ¼ 9 Hz), 6.99–7.07 (2H, m),
7.42 (1H, dd, J ¼ 9, 2 Hz), 7.47 (1H, d, J ¼ 9 Hz), 7.53 (1H, d,
J ¼ 9 Hz), 7.60 (1H, d, J ¼ 2 Hz), 7.85 (2H, d, J ¼ 9 Hz), 7.92
(1H, d, J ¼ 9 Hz), 8.14 (1H, d, J ¼ 9 Hz), 8.56 (1H, d, J ¼ 2 Hz);
13C NMR (75 MHz, CDCl3): ꢀ 56.6, 56.9, 114.5, 115.0, 115.1,
117.5, 118.1, 118.2, 121.9, 123.5, 125.9, 126.4, 127.3, 128.7,
129.0, 130.1, 130.5, 131.1, 131.4, 132.4, 132.9, 133.0, 135.6,
143.4, 149.8, 154.8, 193.8; IR (KBr): 1653, 1612, 1592, 1501,
1477, 1246 cmꢃ1; HRMS [M + H]þ m=z 865.2772 (calcd for
7
8
C
58H41O8, 865.2801).
.
.
9
Crystal data for cyclic dimer 7: C58H41O8 3C4H8O2 CH4O Mr ¼
1160:25, Orthorhombic, space group C2221, a ¼ 13:1320ð2Þ,
3
˚
˚
b ¼ 17:5489ð3Þ, c ¼ 26:8074ð5Þ A, V ¼ 6177:82 A , Z ¼ 4,
Dcalcd = 1.2475(1) g cmꢃ3, T ¼ ꢃ155 ꢂC, R1 ¼ 0:09 (all data),
wR2 ¼ 0:26 (all data), GOF = 1.074 for 5646 reflections and 375
parameters.
The bidirectional tunnel-like structure assembly thus ob-
tained displays the novel area for finely designed higher ordered
organic solid, especially that composed of only C, H, and O
elements. In a natural course, the findings mentioned above
imply the significance of further investigation of the isomeric
10 K. Campbell, C. J. Kuehl, M. J. Ferguson, P. J. Stang, R. R.
Tykwinski, J. Am. Chem. Soc. 2002, 124, 7266.
Published on the web (Advance View) May 24, 2008; doi:10.1246/cl.2008.660