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Chiral Macrobicyclic and Macrotricyclic Ligands.

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The extent to which the four methyl groups in ( 4 ) contribute
to stabilization of the skeleton ( I b) is difficult to estimate.
However, the effect cannot be very large since the intermediate
3,4,5,6-tetramethylbenzocyclobutadieneundergoes immediate
angular dimerization['O1like ( I a ) .
3,4,5,6-Tetramethyi-l,2-diphenylbenzocyclobutadiene
(4)
All operations and measurements have to be performed under
nitrogen. Asolutionof(3)(3.1 g, lOmm~l)[~Iin
light petroleum
(b.p. 110-130°C, 150ml) is first heated to 110°C (oil bath
175-180°C) for 9min and then immediately cooled in an
ice bath. After complete removal of solvent (3-1 torr at
room temperature) the residue is rapidly dissolved in light
petroleum (b. p. 60-80°C) and freed from sparingly soluble
( 5 ) (ca. 30%) by filtration. The filtrate is concentrated (14 torr
at room temperature) until the onset of crystallization. The
mixture is then cooled to - 20°C and the carmine red needles
filtered off under suction (m. p. 120°C, dec.); yield 20%.
We present here our results on the synthesis and on some
properties of the chiral macrobicyclic and macrotricyclic molecules ( 4 ) and ( 6 ) , which may function as ligands for metal
cation^".^.^] as well as for molecules[']. The binaphthyl
group has been selected as center of chirality in the recently
described chiral macrocyclic polyethers[*.91. Not only does
it introduce marked chirality into a molecule but is also
quite easily prepared and resolved["], and confers increased
lipophilicity upon the system. Other chiral groups may be
used for similar purposes"
(Za), X = OH
Received: April 1. 1974 [Z 17 IE]
German version: Angew. Chem. 86,412 (1974)
[ l ] M . P. Coca and M . J . Mitchell: Cyclobutadieneand Related Compounds.
Academic Press, New York 1967; D. Seebach in Houben- Weyl-Miiller: Methoden der Organischen Chemie. Thieme, Stuttgart 1971, Vol. 1V/4, p. 231.
[2] See, e.9 : M. J . S . Dewar and G. J . Cleicker, Tetrahedron 21, 1817
(1965); A. E Meyer, ibid. 24, 6215 (1968), and further references therein.
[3] Unsuccessful attempted synthesis of ( 1 b j : M . Stiles, U . Burckhardt,
and A . Haag, J. Org. Chem. 27,4715 (1962).
[4] A . Huth, H. Straub, and E. Miilfer, Liebigs Ann. Chem. 1973, 1893;
A . Huth, Dissertation, Universitat Tiibingen 1972.
[5] If ( 4 ) is trapped in solution directly with reactive dienophiles, the yields
of the adducts exceed 80% in some cases [4].
[6] The UV spectra were each recorded 3min after dissolution of (4). The
extinction coefficients of the bands change when the solution is allowed
L
8 2 1 8 increasing and E Z , ~and ~
4 decreasing.
~
8
The decrease
to stand, E ~ O and
in 8 4 b ~of a ca. 0.4mM solution affords a half-life of ca. 23min for ( 4 )
at room temperature.
(Zb), X = C1
Optically active (S)-(-)-1,I'-bi-2-naphthol ( I ) [m.p. 206°C;
THF); -39.6" (~=1.05, THF)'"]]
has been obtained via resolution of its phosphoric acid derivative with cinchonine" 'I and recrystallized from toluene.
Condensation of ( 1 ) with bromoacetic acid in refluxing methanol in the presence of potassium carbonate affords the optically active dicarboxylic acid ( 2 a ) [m.p. (racemic) ~ 2 1 0 ° C ;
[u]g -36" (c=0.22, acetone); yield 95x1. The corresponding dichloride (2b) is obtained by treatment with oxalyl chloride in benzene ; the yield is quantitative (NMR spectrum)
and the oily product is used without further purification;
the crystalline racemic dichloride has m. p. 73-75 "C.
[a]::, -40" (C=O.5,
[7] Correct elemental analyses were obtained for ( 4 ) and (6).
[S] This does not apply to ( 2 b ) : M . P. Caua and H. E Hwang in ref.
[l]. p. 246.
[ 9 ] G. Quinckert, K . Opitz, W-W Wiersdorff, and M. Finke, Liebigs Ann.
Chem. 693,44 (1966).
[lo] H. Straub, unpublished results.
x
Chiral Macrobicyclic and Macrotricyclic Ligands[**]
By Bernard Dietrich, Jean-Marie Lehn, and Jacques Simon[*]
Complexation ofalkali and alkaline-earth cations['] by macrocyclic[z1,macrobicyclic". '], and macrotri~yclic[~61 ligands
leads to the formation of inclusion complexes of the cryptateL3]
type. The design of molecular receptors capable of molecular
recognition represents the next step in the elaboration of synthetic ligands whichmay selectively complex a given substrate
molecule[s~61.
An interesting special case is the design of optically active substances capable of functioning as chirospecijic
molecular receptors; i. e. substances which display preferential
complexation of one optical antipode of a given substrate.
Optically active macrocyclic amino-ether['' and polyether[s*91
ligands have been described recently; the latter display
pronounced selectivity of complexation of chiral
Such behavior is also known for the natural macrocyclic
polysugars, the cyclodextrins[lO1.
[*] Dr. B. Dietrich, Prof. J. M. Lehn, and J. Simon
Institut de Chimie, Universite Louis Pasteur
1 rue Blaise Pascal, 67-Strasbourg (France)
ERA 265 du C.N.R.S.
[**I Molecular Receptors, Part 3. Reported in part at the First Fall Organic
Chemistry Meeting of the American Chemical Society, October 1-3, 1973,
North Falmouth, Massachusetts.-Part 2: ref. [6].
406
(4a). X = 0
(4b), X = Hz
Condensation of (2b) with the macrocyclic diamine (3)[31
under high dilution conditions[31gives the macrobicyclic dicarboxamide ( 4 a ) [m.p. 190--192°C; [a]6' -92" (c=0.41,
CHCI3); yield 60%]. Reduction of (4a) with diborane in
THF['I leads to the optically active macrobicyclic diamine
(4b) [oil; [aid' - 151" (c=0.39, CHC13);yield 90%].
(6a). X
(6b), X
= 0
= Kz
High dilution condensation[31of (2b) with the diamine ( 5 ) [ ' ]
affords the tetracarboxamide ( 6 a ) [glass; [a];' -42" (c=O.23,
acetone); yield 50%]. Diborane reduction[31 of ( 6 a ) gives
Angrw. Chem. internat. Edit. 1 Vol. 13 (1974) 1 No. 6
the optically active macrotricyclic tetraamine ( 6 b ) [oil; [a]&'
-68" (c=0.17, CHC13); yield 90%]. Compounds ( 4 b ) and
( 6 b ) were further purified by lyophilization in benzene/methanol (9: 1). The spectral (NMR; mass) and analytical data
of the compounds described are in agreement with the structures (2), ( 4 ) , and ( 6 ) . Control experiments were performed
to ensure that no detectable racemization occurs in the course
of the condensation and reduction steps leading to ( 2 a ) ,
( 4 b ) , and ( 6 b ) .
Hydrolysis of the borane-amine adducts formed in the diborane reductions was not effected under reflux (as in ref.[31);
instead the products were treated with a mixture of T H F
and 9 N HCl ( 1 : 1 ) for one hour at 25°C. The amines ( 4 h )
and ( 6 b ) were extracted with toluene after the solution had
been rendered basic.
Compounds ( 4 ) and ( 6 ) are the first optically active, synthetic
macrobicyclic and macrotricyclic substances to be reported.
Macrotricyclic systems contain a large intramolecular cavity
which should be capable of accommodating substrate molec u l e ~ [ ~ .Molecular
~'.
models show that the cavity of compounds ( 6 ) forms a deep (about 8A) chiral pocket. Like
their previously described achiral analogs['. 3 . 51, ( 4 b ) and
( 6 h ) complex various metal cations.
Formation of complexes between ligand ( 4 b ) and the bromides of sodium, potassium, rubidium, and cesium leads to
marked changes in the NMR and UV spectra of the ligand.
An interesting effect is found for the optical rotation. The
element of chirality is the angle between the two naphthalene
systems in the binaphthyl fragment. Complexation of a metal
cation inside the molecular cavity is expected to affect the
optical activity of ( 4 b ) both by electronic effects and by
modification of the chirality angle. The latter factor may be
expected to display a gradual variation as the size of the
included cation increases from sodium to cesium and deforms
the ligand, the charge remaining constant. This is indeed
observed:
f36, -9, -130, and -215' (in CHC13)
for the cryptate complexes of ( 4 b ) with NaBr, KBr, RbBr,
and CsBr, respectively. Assuming that the value measured
for Na' contains both the effect of cation charge and that
of conformational change on cation inclusion, the variations
observed for K + , R b + and Cs+ may be related to a progressive
opening of the dihedral angle caused by the increase in cation
size. Complexation also leads to large changes in the circular
dichroism spectra of the ligand.
The macrotricyclic ligand ( 6 b ) also shows pronounced NMR
spectral changes on cation complexation (Na ', K '). The specific rotation is -25 and 0" for the Na' and K+ complexes
respectively. Like the previously described tetraamides['. 'I,
( 6 a ) does not form stable complexes with alkali metal cations.
However, it contains amide (like peptides) and ether binding
sites and has been found to extract ammonium salts from
water solution into chloroform[' 31. Both cation and anion
properties are expected to affect such ion pair binding. So
far only low optical resolution (about 10% optical purity) of
racemic substrates has been achieved"'].
Depending on the properties desired, additional structural
features may be introduced into these ligands (e.g. cationic
or anionic sites for substrate-ligand ion pairing and catalytic
sites for specific reactions), as has been done for macrocyclic
polyethers (carboxylate sites)['. 91 and for macropolycyclic
amino-ethers (carboxylate, imidazole, and hydroxamate
sites)" '1.
[3] B. Dietrich, J . M. Lrhn, J . P. Saut;age, and J . Blanzat. Tetrahedron
29. 1629 (1973): B. Dietrich, J . M . Lehn. and J . P. Soul-age, ihid. 29, 1647
(1973), and references therein.
[4] J . Cheney, J . M . Lrhn, J . P. SuuLagr, and M. E. Stubbs, J. C. S. Chem.
Commun. 1972, 1100.
[5] J . M . Lehn, J . Simon, and J . Wagner, Angew. Chem. N5, 621 (1973);
Angew. Chem. internat. Edit. 12, 578 (1973).
[6] J . M . Lrhn, J . Simon, and J . Wagner, Angew. Chem. 85, 622 (1973);
Angew. Chem. internat. Edit. 12, 579 (1973).
[7] F. Midl and F. Gaeta, J. C. S. Chem. Comm. 1972, 107.
[8] E . P. Kyba, M . G. Siege/, L. R. Souso, G. D. E Sogah, and D. J . Cram,
J. Amer. Chem. SOC. 95. 2691 (1973): R. C. Hrtgrson, J . M Timko, and
D. J . Cram, ibid. 95, 3023 (1973); G. M . Gokel and D. J . Cram. J. C. S.
Chem. Comm. 1973,481.
[9] E . P. Kyha, K . Koga, L. R. Sousa, M . G . Siege/. and D. J . Crom, J.
Amer. Chem SOC.95, 2692 (1973); R. C . Hdgeson, K . Koga, J . M . Timko.
and D J . Crom, J. Amer. Chem. SOC. 95, 3021 (1973).
[ 101 F Crurnrr, Angew. Chem. 68, 115 (1956); F. Crainer and G. Muckensm,
Angew. Chem. 78, 641 (1966); Angew. Chem. Internat. Edit. 5, 601 (1966):
Naturwissenschaften 54,625 (1967), and relerences therein; R. Bredow. Chem.
SOC. Rev. I , 553 (1972); H . P Brnsrhop and G . R . Van deii Brry, Chem.
Commun. 1970, 1431; M . Mihofajczyk. J. Drahowic:, and F. Cromrr. Chem.
Commun. 1971, 317.
[Ill
[12]
J . Jacques, C . Fonqtrey, and R. Vitrrho, Tetrahedron Lett. lY71, 4617.
[/. Prefog, personal communication.
[13] J . M . Lehn and J . Simoir, to be published.
[I41 J . M.Lrhn, F. Montacon, P. Mtuli, and J . Wagner, unpublished results.
A Novel Method for the Stereoselective Synthesis of
trans Olefins
By Kiyosi Kondo, Akira Negislii, and Daiei Tunernoto[*]
We report herein a new and useful two-step synthesis of trans
olefins from alkyl halides R'-X
and y-substituted allylphosphonates, e. g. diethyl 2-butenylphosphonate ( I a ) and
diethyl (3-methyl-2-buteny1)phosphonate
( 1 bf .
='&I.[
.____
Received: April I , 1974 [Z 23 IE]
German version: Angew. Chem. 86, 443 (1974)
[ l ] J. M . Lehn, Struct. Bonding 16, 1 (1973).
[2] C. J . Pedersen and H . K . Frensdorff, Angew. Chem. 84, 16 (1972); Angew.
Chem. internat. Edit. 2 1 , 16 (1972).
Angew. Chum. internat. Edit. 1 Vol. 13 (1974) / N o . 6
(IN). R
= H
( l h ) , R = CH3
Lz A l l l ,
H 3 C C F l I /H
/C
H
=
c,
131
T i1
There are several reports in the literature describing electrophilic capture of phosphonate-stabilized carbanions by alkyl
halides or ketones[']. However, those adducts do not appear
to be satisfactorily transformed into olefins'". We found that
lithio derivatives of y-substituted allylphosphonates such as
( 1 a ) or (1 b ) were alkylated at the a position exclusively
by a variety of alkyl halides. Furthermore, the adducts (2)
undergo a smooth reductive fission to olefins (3) on treatment
with LiAlH4 in dry ether at 0°C for a few hours. The IR
spectra exhibited a strong absorption at 965 cm- characteristic of trans olefins ; their homogeneity was confirmed by gas
chromatography using several different columns.
Thus the newly found hydrogenolysis of allylic phosphonates,
in conjunction with alkylation as described above, constitutes
an excellent and generally applicable method for the stereoselective synthesis of trans ole fin^[^] (Table 1).
A further advantage of the method derives from the fact
that even if the starting material ( I ) is not stereochemically
[*I
Dr. K. Kondo, Dr. A. Negishi, and DipLChem. D. Tunemoto
Sagami Chemical Research Center
4-4-1, Nishionuma, Sagamihara
Kanagawa, 229 (Japan)
407
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