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Cation-Induced Charge-Transfer Absorption of Intramolecular Quinhydrones with Oligooxaparacyclophane Structure.

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1,n:l
2.n=2
3,n:3
bn=L
diethylene glycol ditosylate (sodium hydride, tetrahydrofuran, dilution principle; 20% yield). Analogously, reaction
of 1,3-bis(4-bromomethyl-2,5-dimethoxyphenyl)propane~41
with tri-, tetra-, and pentaethylene glycol, respectively, led
to 6 (m.p. 88-89 "C, 35%
7 (m.p. 82-85 "C,
21%)[3"1,and 8 (m. p. 67-69 "C, 22%)13"].
Fig. 1. Structure of complex 3 in the crystal (the phenyl groups are represented by their first C-atoms). Selected bond lengths [.&] and bond angles ["]:
RuPl 2.247(2), RuP2 2.229(2), RuC 2.169(6), RuCp (average) 2.246; CRuPl
87.4(2), CRuP2 84.6(2), PlRuP2 84.6(1), PlRuCp* 135.4, P2RuCp* 129.8,
CRuCp* 119.0 (Cp*=centroid of the q5-C5H5ring).
the hydrido complexes [CpRuH(prophos)] 5 [&(Pa)=98.1,
6(Pb)=77.2,
Jp_p=30.0
Hzl4]; &(Ru)H= - 13.22,
JPPH
=29.4 and 37.5 Hz] and 6 [&(Pa)= 104.3, 6(Pb)=85.7,
Jp-p=22.9 Hz14]; &(Ru)H= - 13.05, JP--H=32.0 Hz], respectively, are formed. These reactions also are stereospecific within the NMR detection limits. The stereochemistry
of the p-hydrogen elimination should be clarified by an Xray structural analysis of 5 or 6.
Received: November 15, 1982 [Z 202 IE]
German version: Angew. Chem. 95 (1983) 322
[ l ] H. Brunner, G. Wallner, Chem. Ber. 109 (1976) 1053. PPh,R*=(S)Ph2PN(CH3)CH(CH3)Ph.
[2] G. Consiglio, F. Morandini, G. Ciani, A. Sironi, M. Kretschmer, J . Am.
Chem. Soc., in press.
[3] M. D. Fryzuk, B. Bosnich, J. Am. Chem. SOC.100 (1978) 5491.
[41 The "P-NMR signals were not assigned.
[ S ] H. Lehmkuhl, J. Grundke, R. Benn, G. Schroth, R. Mynott, J . Organomet.
Chem. 217(1981) CS.
Cation-Induced Charge-Transfer Absorption of
Intramolecular Quinhydrones with
Oligooxaparacyclophane Structure"'
By Helmut Bauer, Jan Briaire, and Heinz A . Staab*
The dependence of the charge-transfer (CT) absorption
on distance, orientation, and mutual fixation of donor and
acceptor components in quinhydrones of the [n.n]paracyclophanes (n = 2-5) were studied[',']. For the intramolecular quinhydrones 1-4, which are oligooxa derivatives of
[3.m]paracyclophanes (m=9, 12, 15, and 18), it was anticipated that donor and acceptor are not optimally arranged
for CT transition due to the width and flexibility of the
macrocyclic rings. Because of the crown ether partial structure of these molecules, however, complexation of cations
with suitable ionic radius should result in a greater rigidity
of the macrocycle and in an approach of donor and acceptor regions; as a consequence, a change in CT-absorption was expected.
The synthesis of 1-4 starts from tetramethoxyoligooxaparacyclophanes 5-8. 5 (m.p. 85-95 "C, mixture of pseudoortho and pseudogerninal
was obtained from
4,4'-trimethylenebis(2,5-dimethoxybenzyl alcohol)[41 and
5,nzl
6,n=2
7.17~3
0. n = L
Partial oxidative demethylation of 5-8, respectively,
with diammonium he~anitratocerate'~]
yielded 1 (42?'0)[~~',
2 (65?'0)[~"',3 (97?'0)'~~],
and 4 (82%)13'], respectively.
The UV/VIS spectrum of 3 has a CT absorption
(L,,,=462 nm, ~ = 3 2 4 ;in chloroform), which upon complexation with N a + (NaSCN, chloroform) shows a remarkable increase in intensity (&= 874, Fig. I), together
with a bathochromic shift of 16 nm. This change in the C T
absorption, which is also visually easily observable, is reversed by addition of the stronger ligand 4,7,13,16,21-pentaoxa- 1,I0-diazabicyclo[8.8.5]tricosane (CryptofixB 221). To
explain this complexation effect we assume that the reaction 3-9 results in a conformational change which brings
the donor and acceptor regions of the molecule closer together. This is supported by the fact that, relative to those
of 3, in 9 the signals of the two benzoquinone protons in
the 'H-NMR are shifted to highfield by A&=0.10 and 0.23
ppm (in CDCI3) as a result of a stronger transannular anisotropy effect of the neighboring aromatic ring. Crystals of
9 may be obtained (m. p. 152- 153 "C, decomp.) from a solution in chloroform/methanol by precipitation with ether.
Me0
700
I
360
[*] Prof. Dr. H. A. Staab, Prof. Dr. H. Bauer, J. Briaire
Abteilung Organische Chemie
Max-Planck-Institut fur medizinische Forschung
Jahnstrasse 29, D-6900 Heidelberg 1 (Germany)
334
0 Verlag Chemie GmbH, 6940 Weinheim, 1983
A
:.O)i
I
LOO
500
600
hrnrn]
-
700
Fig. I . Absorption spectra of 3 and 9 (conc. 1 . 7 2 ~lo-' rnol/L in chloroform).
0570-0833/83/0404-0334 $02.50/0
Angew. Chem. I n t . Ed. Engl. 22 (1983) No. 4
With the lower analogues 1 and 2, N a f ions do not
show any significant effect on the CT absorption; for the
higher analogue 4 (/lcr=442 nm, ~ = 2 1 3 )the complexation effect of N a + with A&= 162 is significantly smaller
than for 3. K + ions change the CT absorption of 1 and 2
scarcely at all, and that of 3 significantly less than Na+
ions; with 4, however, they result in an enhancement of
the intensity by A&= 139 and in a bathochromic shift of 23
nm. It seems to us that in compounds 1-4 a principle of
cation-selective ligands with a “built-in CT indicator” is
realized which may be of some general interest.
Received: December 8, 1982;
supplemented: February 14, 1983 [Z 219 IE]
German version. Angew Chem 95 (1983) 330
CAS Registry numbers:
1, 85083-46-1 ; 2, 85083-47-2; 3, 85083-48-3; 4, 85083-49-4; 4 . N a + , 8508344-9; 4 . K ’ . 85083 45-0; 5, 85083-50-7; 6, 85083-51-8; 7, 85083-52-9; 8,
85083-53-0: 9, 85083-54.1.
[ I ] Electron Donor-Acceptor Compounds, Part 34.-Part 33: H. A. Staab, C.
P. H e n , C . Krieger, M. Rentea, Chem. Ber.. in press.
[2] H. A. Staab, W. Rebafka, Chem. Ber. 110 (1977) 3333; H. A. Staab, C. P.
H e n , Angew. Chem. 89 (1977) 839; Angew. Chem. Int. Ed. Engl. 16 (1977)
799; H. A. Staab, A. Dohling, C. Krieger, Liebigs Ann. Chem. 1981, 1052,
and references cited therein.
131 a) Elemental analyses and spectroscopic data correspond to the structure
suggested; b) 1 : orange-red crystals, m.p. 120-122°C (from ethyl acetate/cyclohexane, 2 : l ) ; MS: m/z=416 (IOOYo, M + ) ; ‘H-NMR (CDCI,,
80 MHz): 6=2.00-3.25 (m, 6H), 3.62-3.82 (m, 14H), 4.33 (d, J = 2 Hz,
2H), 4.23, and 4.62 (AB, J = 1 3 Hz, 2H), 6.17 ( s , l H ) , 6.35 (t. J = 2 Hz,
1 H), 6.45 ( s, 1 H), 6.68 (s, 1 H).-c) 2 : orange-red crystals, m. p. 68-70°C
(from etherln-heptane); MS: m/z=460 (lOOo/o, M + ) ; ‘H-NMR (CDCI,,
80 MHz): 6=2.00-2.80 (m, 6H), 3.69 ( s , 18H), 4.27 (d, J = 2 Hz, 2H),
4.48(~,2H),6.13(t,J=lHz,1H),6.41(t,J=2Hz,lH),6.46(~,
IH),6.68
( s , 1 H).-d) 3 : orange-red prisms, m.p. 71-72°C (from ether/n-heptane);
MS: rn/z=504 (100%, M + ) ; ’H-NMR (CDCI,, 80 MHz): 6 = 1.80-2.25
(m. 2H),2.25-2.80(m, 4H), 3.50-3.85 (m, 22HL4.31 (d, J = 2 Hz, 2H),
4.52 (S, 2H), 6.31 (Y’, J = 1 Hz, I H), 6.54 (s, 1 H), 6.60 (t, J = 2 Hz, 1 H),
6.81 ( s , 1 H).-e) 4 : orange-yellow crystals, m.p. 88-90°C (from ethyl
acetate/cyclohexane, 3 : 1); MS: m/z=548 (lo%, M + ) , 177 (IOOYo); ‘HNMR (CDC12, 80 MHz): 6 = 1.91 (quint., J = 7 Hz, 2H), 2.42 (t, J = 7 Hz,
2H),2.86(t,J=7Hz,2H),3.58-3.70(m,20H),3.71(s,3H),3.74(s,3H),
4.34(d,J=2Hz,ZH),4.52(~,2H),6.42(t,J=l Hz,lH),6.59(s,IH),
6.74 (t, J = 2 Hz, 1 H), 6.87 (s, 1 H).
[4] Starting from 1,3-bis(2,5-dimethoxyphenyl)propane(R. E. Moser, H. G.
Cassidy, J. Org. Chem. 30 (1965) 2602) chloromethylation and hydrolysis
yielded 4,4’-trimethylenebis(2,5-dimethoxybenzylalcohol) [3a]; bromomethylation yielded 1,3-bis(4-brornomethyI-2,5-dimethoxyphenyl)propane [3a].
[5] General procedure for the synthesis of 1-4: A solution of diammonium
hexanitratocerate (0.8 mmol) in 10 m L water was added to a stirred solution of 5, 6 , 7, or 8 (0.4 mmol) in 40 m L acetonitrile at room temperature. After 20 min the reaction mixture was extracted with dichloromethane; the extract was dried on magnesium sulfate, evaporated, and the
residue chromatographed on silica gel using cyclohexane/ethyl acetate.
BOOK R E V I E W S
’Elektronenstruktur organischer Molekule. Grundbegriffe
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This book by M . Klessinger is the first volume of a sixpart series entitled “Physikalisch Organische Chemie” and
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Angew. Chem. 1111.Ed. Engl. 22 (1983) No. 4
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