close

Вход

Забыли?

вход по аккаунту

?

Direct Synthesis of Metal-Free 1 8-Dihydrotetraaza-[14]annulenes Utilizing the Metal-Template Effect.

код для вставкиСкачать
Direct Synthesis of Metal-Free l,&Dihydrotetraaza[14]annulenes Utilizing the Metal-Template Effect[**]
By Gerhold Miihmei and Eberhard Breitmaier ['I
Metal chelates of type ( 5 ) , M = Ni, are formed by cyclocondensation of enediamines (1) and 3-ethoxyacroleins (2) in
the presence of nickel(11)ionsc1].This synthesis, giving yields
of about 90 %, is facilitated by the favorable arrangement
of two enediamine groups in complex (3) and by the stability
of the resulting macrocyclic metal chelate (metal-template
effect121). However, the metal-free macroheterocycle ( 4 ) is
often preparable in only poor yield from ( 5 ) .
During our experiments concerned with the preparation of
metal chelates 6,13-dialkyl-1,8-dihydro-1,4,8,11
-tetraaza[14]annulene-2,3,9,1O-tetracarbonitriles
by the reaction sequence
( I ) + ( 3 ) - ( 5 ) we found that the metal-free macroheterocycles ( 4 ) are formed directly if the metal ion M"+ has an
ionic radiusc3]significantly smaller or larger than 70pm. Thus
we obtained complexes of type ( 5 ) with Ni2+ (r=69pm),
C o 2 + , Cu2+ (both with r=72pm), Fez+, and Zn2+ (both
with r=74pm). On the other hand, Mg2+ having r=66pm
and M n 2 + having r = 80pm already afford the macroheterocycle (4). In view of the expected selectivity of the ligands
( 4 ) this finding initially appears trivial. It is however of preparative significance that the yields of ( 4 ) obtained by the
same reaction is conducted without metal ions (see Table
1). Of decisive importance for the effective synthesis of ( 4 )
is the low selectivity of this ligand for the (oversize or undersize)
metal ion. To our knowledge this variant of metal-template
synthesis has not been employed previously.
Procedure
Synthesis of (4e): Compound ( 1 ) (4.32g, 40mmol) and
Cr2(S04)3.1 8 H 2 0 (7.16g, 10mmol) are dissolved in anhydrous ethanol (50 ml) and heated for 30 min under argon. After
brief cooling, a solution of (2e) (6.24g, 40 mmol) in anhydrous
ethanol (10ml) is added and the mixture is heated under
reflux for an additional 11 h. After cooling the crude product
is filtered off under suction, washed thoroughly with methanol,
and dried. Further purification is accomplished by extraction
for 16 h with toluene, in which (4e) dissolves with an intense
green color when hot. On cooling a sample of (4e) is obtained
(4.9 g, 61 %) which proves to be pure on thin-layer chromatography.
Received: July 19, 1978 [Z 62 IE]
German version: Angew. Chem. 91). 818 (1978)
CAS Registry numbers:
( I ) , 1187-42-4; ( Z a ) , 42588-57-8; ( 2 b ) , 30989-75-4; ( 2 c ) , 21037-71-8; ( 2 d ) ,
30989-77-6; ( Z e ) , 21037-73-0; (Zf), 30989-79-8; (3) (MX = Cr2(S0&. 6778458-1 ; (3) (MX=Mg(ClD&, 67784-56-9; ( 3 ) (MX= MnCI2), 67784-54-7;
( 4 a ) , 67773-70-0; ( 4 b ) , 67773-71-1 ; ( 4 c ) , 67773-72-2; ( 4 d ) , 67773-73-3;
( 4 e ) , 67773-74-4; ( 4 f ) . 67773-75-5; Cr2(S04)3, 10101-53-8; Mg(C104)z,
10034-81-8; MnCI>,7773-01-5
I . Kohlmeyer, E. Lorch, G. Bauer, E. Breitmarer, Chem. Ber. 111, 2919
(1 978).
[2] H . Hiller, P . Dimrorh, H . Pfitzner, Justus Liebigs Ann. Chem. 717, 137
( 1 968): P. Cliiir e. C I . . //,,ii~,,l,,,ii~ii(,.
Chem. Commun. 196Y. 279: C.
L . H o i i ~ ~ ~ / ~ i nChem.
w i r ~ ~Ind.
. (London) IY75. 350: R. Mii//w,
D . Wijhrle,
Makromol. Chem. 176, 2775 (1975); 177, 2241 (1976); E. Lorch, E. Breitmaier, Chem.-Ztg. 99, 87 (1975); D. St. C. Black, P. W. Kortr, Aust.
J . Chem. 25, 281 (1972); D. Sr. C . Black, A . J . Hartshorn, J. Chem.
SOC.Chem. Commun. 1972, 706; E. G . Jiiger, Z. Anorg. Allg. Chem.
364, 177 (1969); F . A . L'Eplattenier, A. Pugin, Helv. Chim. Acta 58,
917 (1975).
[3] Handbook of Chemistry and Physics. 52nd Edit. The Chemical Rubber
Co., Cleveland, Ohio 1972, p. F-171.
[I]
R
R
Synthesis of 5'-0-Glycos yl-vibo-nucleosides [**I
sequence (1) + (3) + ( 4 ) in a one-pot reaction in the presence
of certain metal ions are considerably higher than when the
Table 1 . Template effect of metal ions on the yield of ( 4 ) . Reactions performed
in ethanol.
MX
Cr2(S0&. 1 8 H z 0
Mg(C104)~11
.
MnClZ.4HzO[a, h]
~
r(M"+)
[pml
R
63
CH3
C2H5
n-CsH7
i-C3H7
n-C4H9
n-C5HII
n-C4Hy
n-C4H9
n-C4Hy
66
80
-
t [h]
( 4 ) , Yield
["/.I
11
11
11
11
11
11
29
30
11
48
59
60
56
61
59
53
55
14
(4a)
(46)
(4c)
(4d)
(4e)
(4.f)
(4e)
(4e)
(4e)
By Frieder W Lichtenthaler, Yuzuru Sanemitsu, and Toshihiro
Nohara"]
Certain bacteria, such as Breuibacterium ammoniagenes[']
and Bacillus sp. No. 102['], have the potential for elaborating
5'-0-hexosylated nucleosides of type (1)-(3),
a novel group
of bacterial metabolites that can vary in the nucleobase (hypoxanthine and guanine), in the hexose portion [glucose (1 a ) ,
(1 b ) ; maltose (2n), (2b); and galactose ( 3 a ) ] , and in the
configuration of the intersaccharide bond (a-and 0-linkage).
Analogs with adenine and uracil as the aglycon, i. e. (1 c)13],
( 3 cjc4],and (3d)I5l,have also been obtained yet by the action
of bacterial enzyme preparations on maltose and o-nitrophenyl a-D-galactoside and the respective ribo-nucleoside.
The unknown biological role of these glycosylnucleosides
prompted us to embark on their chemical synthesisc6],which
~
[a] ( 4 e ) is obtained analytically pure. [b] Reaction performed in methanol.
[*] Prof. Dr. E. Breitmaier, DipLChem. G. Muhmel
Institut fur Organische Chemie und Biochemie der Universitat
Gerhard-Domagk-Strasse 1, D-5300 Bonn (Germany)
[**I This work was supported by the Ministerium fur Forschung und Wissenschaft des Landes Nordrhein-Westfalen.
772
[*I
Prof Dr. F. W. Lichtenthaler, Dr. Y.Sanemitsu, Dr. T. Nohara
Institut fur Organische Chemie und Biochemie der Technischen Hochschule
Petersenstrasse 22, D-6100 Darmstadt (Germany)
[**I Nucleosides, 35th Communication. We gratefully acknowledge supp(w1
of these investigations by the Deutsche Forschungsgemeinschaft and tlic
Fonds der Chemischen 1ndustrie.-Part 34: [7].
Angew. Chem. Inr. Ed. Engl. 17 ( 1 9 7 8 ) N o . 10
Документ
Категория
Без категории
Просмотров
1
Размер файла
126 Кб
Теги
dihydrotetraaza, effect, synthesis, annulene, free, metali, direct, template, utilizing
1/--страниц
Пожаловаться на содержимое документа