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The Cyclodecapentaene System.

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Triphenylphosphine N-Acetylglycosylimides and
N,N'-Bis(ace tylglycosy1)carbodiimides
By Dr. A. Messmer, Dip1.-Cheni. T. Pint&, and
Dip1.-Chem. F. SzegB
Central Research Institute of Chemistry of the Hungarian
Academy of Science, Budapest (Hungary)
Research on the application to sugar chemistry of the
phosphine imide reaction of Staudinger [1] led to the synthesis of phosphine-imido derivatives of sugars. 2,3,4,6Tetra-0-acetyl-p-D-glucosyl azide ( I ) [2] reacts with triphenylphosphine (2) in absolute ether even at room temperature with loss of a molecule of nitrogen t o give triphenyl(3)
phosphine N-(2,3,4,[email protected]~-glucosyl)imide
which forms macroscopic crystals. The structure of (3) was
proved by Zemplen hydrolysis [3] and by its reaction with
p-nitrobenzaldehyde to give N-(p-nitrobenzylidene)-2,3,4,6tetra-0-acetyl-p-D-glucosylamine
The syrupy product obtained from (5) by Zemplen hydrolysis
is to be regarded as N,N'-bis-(P-D-glucosyl)isourea methyl
ether and the crystalline substance obtained from this by
acetylation as N,N-bis-(2,3,4,[email protected]~-glucosyl)isourea methyl ether (m.p. 161 "C, [a]D = -2.7 in CHC13).
The bisglycosylcarbodiimides prepared and the bisglycosylurea derivatives obtained under Bredereck's conditions [S]
are shown in Table 2.
Table 2. Properties of bis(acetylglycosy1)carbodiimides and bis(acetylg1ycosyl)carbainides.
glucosyl2,3,4,6-Tetraacetyl13-a-galactosyl- 1 16.9
2,3,4-Tri-O-acetyl-~-~-xylosyl- I39
130- 145
I :;;"
in CHCI3
Received, January 2nd, 1964
IZ 6521477 IE]
German version: Angew. Chem. 76, 227 (1964)
The triphenylphosphine-imido derivatives of acetylated
sugars prepared in this way are shown in Table 1.
Table 1. Properties of triphenylphosphine N-acetylglycosylimides.
[ CI
[ l ] H . Staudinger and E. Hauser, Helv. chim. Acta 4 , 861 (1921).
[2] A . Bertho, Ber. dtsch. chem. Ges. 63, 836 (1930).
[3] G. Zempl&, Ber. dtsch. chem. Ges. 56, 1705 (1923); 59. 1255
(1926); 69, 1827 (1936).
[4] A. Bertho and J . Maier, Liebigs Ann. Chem. 498, 50 (1932).
[S] E. Fischer, Ber. dtsch. chem. Ges. 47, 1377 (1914);A . Miiller
and A . Wilhelms, ibid. 74, 698 (1941).
[6] F. Miclreel and W. Brrtnkhorst, Chem. Ber. 88, 484 (1955).
[7] E. Schmidt and F. Moosmiiller, Liebigs Ann. Chem. 597, 235
[8] H . Bredereck and E. Re$, Chem. Ber. 81, 426 (1948).
[9] R . B. Johnson and W. Bergmann, J. Amer. chem. SOC.54,
3360 (1932).
By analogy to the aliphatic phosphine imides [l], triphenylphosphine N-([email protected])imide (3) reacts with
The Cyclodecapentaene System
C 0 2 or CS2 to give a high yield of the same crystalline substance as is formed from (3) and [email protected]
By Prof. Dr. E. Vogel and Dipl.-Chem. H. D. Roth
isothiocyanate (4) [5]. The analytical data tally with the
formula of N,N'-bis-(2,3,4,6-tetra-O-acetyl-~-~-glucosy1)Institut fur Organische Chemie der Universitat Koln
carbodiimide (5), although the compound is not converted
into a diglucosylurea derivative (6) like a normal carboCyclodecapentaene ( I ) , which contains 10 x-electrons, can
diimide when treated with water [6]or acids, or with methbe expected according to Huckei's rule [I] to possess aromatic
anol in the presence of CuCl [7].
character. High resonance stabilization does not, however,
Thus, as well as (5), the isomeric N,N-bis(tetraacetyl-P-Dseem possible in ( I ) , since the hydrocarbon cannot assume
glucosy1)cyanamide structure must be considered. The ina planar configuration because of overlapping of the van der
frared spectrum does not permit a decision, for the absorpWaals radii of the hydrogen atoms at positions 1 and 6 on
tion line at 2180 cm-1 may come from either the carbodiimide
the trans double bonds.
or the cyano group. Like bistriphenylmethylcarbodiimide [PI,
(5) adds on a molecule of water in benzenelglacial acetic acid,
and N,N'-bis-(2,3,4,[email protected]~-glucosyl~urea
[9] is formed i n 98
yield. This proves the carbodiimide
Angew. Chem. internat. Edit. 1 Vol. 3 (1964)
/ No.3
Atomic models indicate that replacement of the two internal
hydrogen atoms in ( I ) by a methylene group should result
in the formation of an almost, if not completely planar structure of the cyclodecapentaene skeleton.
The synthesis of 1,6-methanocyclodecapentaene(2) [or of
(5)] started from 1,4,5,8-tetrahydronaphthatene[2]. The
triene adds on dichlorocarbene (generated from CHCI3 and
K-t.-butoxide) at the central double bond with a high degree
of selectivity [3] affording (S), m.p. 83-84°C. Sodium in
liquid ammonia converts (3) into ( 4 ) , b.p. 80-81 .C/ll mm,
and this reacts with bromine in the cold to form a tetrabromide,
m.p. 128-129 "C. This compound reacts with bases, e.g. alcoholic KOH, to give a good yield of the desired hydrocarbon
C l l H l o as colorless crystals, m.p. 28-29 "C.
Three structures of the hydrocarbon are possible: a) ( 5 ) ;
b) (2) with a fluctuating structure according to (6) $
(5) ;" (7); and c) (2) with a delocalized Tc-electron system
[(6) (8)I.
( 7)
The ultraviolet spectrum of the hydrocarbon has maxima
at 256my (E = 68000),2 5 9 m y (E = 63000), and 298my
(E = 6200); this suggests an extensive conjugated system [not
compatible with (5)]. The N M R spectrum is particularly
revealing: it shows an AzBz system (8 protons) in the range
2.5-3.2 5 , centred at 2 . 8 r , and a sharp signal at 10.5 T
(2 protons). The absorption of the olefinic protons at very low
field, combined with strong shielding of the CHz-protons
above the peripheral ten-membered ring, can be considered
as evidence [4]for the presence of a ring current and, therefore, for the 1,6-methanocyclodecapentaenestructure (6) to
(8) [ 5 ] . I ,6-Methanocyclodecapentaene is highly strained,
however, and is certainly not an aromatic compound in the
classical sense, because it exhibits olefinic reactivity just like
the [ I 81- and [30]annulenes [6].
Received, January Znd, 1964
[Z 638/464 IE]
German version: Angew. Chem. 76, 145 (1964)
Rearrangements of p-quinols i n trifluoroacetic anhydride
yield the same products. The p-quinolide compound is
dissolved in trifluoroacetic anhydride at room temperature
and, after some time, the reagent is evaporated. On short
hydrolysis with dioxan/water, the phenolic products of rearrangement are usually obtained in quantitative yield and in
pure form. Some of the labile trifluoroacetates of the phenolic
products of rearrangement can be isolated before hydrolysis.
[I] 7'.J . K a / r , J . Amer. chem. SOC.82, 3784 (1960); T . J . Katr
and P . J . Gnrrarr, ibid. 85,2852 (1963), and E. .4. LaLancette and
R . E. Benson, ibid. 85, 2853 (1963) described negatively charged
10-n-electron carbocycles with aromatic character, v i t . the cyclooctatetraene dianion and the cyclononatetraenyl anion.
[2] W. HiickeJ and H . Schlee, Chem. Ber. 88, 346 (1955).
[3] E. Vogel, W. Wiedemann, H. Kiefer, and W. F. Harrison,
Tetrahedron Letters 11, 673 (1963).
[4] L. M . Jackman, F. Sondheimer, Y . Amiel, D . A. Ben-Efrnim,
Y . Gnoni, R . Wolovsky, and A . A . Bothner-By, J. Amer. chem.
SOC.84, 4307 (1962).
[5] A fluctuating structure seems unlikely in view of the position
ofthe olefinic protons in theNMR spectrum; however, it remains
a possibility.
161 F. Sondheimer, R . Wolovsky, and Y. Amiel, J. Amer. chem. SOC.
84, 274 (1962).
p-Toluquinol ( I ) yields toluhydroquinone (2) and cresorcinol (3), but rearrangement of the methyl and tetrahydropyranyl ethers of p-toluquinol yields only the hydroquinone
and no resorcinol derivative. Tetralin-p-quinol (4) and its
ethers rearrange exclusively to 5,8-dihydroxytetralin (5) or its
monoethers, with 1,3-migration of the alkyl substituent. The
acetates and benzoates of p-toluquinol and tetralin-p-quinol
are converted exclusively into the monoesters of the corresponding resorcinol derivatives.
The rearrangements can be explained by assuming that
even a t room temperature trifluoroacetic anhydride contains a sufficient concentration of CF3CO" ions to cause
electrophilic attack on the carbonyl group of the dienone
system and thereby to initiate anionic migration of substituents and consequent aromatization. With p-quinols and
their ethers, the alkyl group migrates preferentially; with
quinol esters, the acyl group migrates considerably faster
than the alkyl group. The exceptional behavior of p-toluquinol (and other monocyclic p-quinols) can be explained
by assuming that esterification of the hydroxyl group competes with the migration of the alkyl group, and that subsequent rapid migration of the attached trifluoroacetyl group
occurs. The high rate of esterification [2] of p-toluquinol and
the small rate of migration of the alkyl group can be established by kinetic measurements [3].
Received, January Znd, 1964
[ Z 640/478 IE]
German version: Angew. Chem. 76, 221 (1964)
[ I ] E. Hei.ker and S . M . A. D. Zajed, Hoppe-Seylers Z . physiol.
Chem. 325: 209 (1961); cf. Angew. Chem. 71, 744 (1959); E.
Hrcker and F. Marks, Naturwissenscharten 50, 304 (1963).
[2] E. Hrtker a n d R. Lattrell. Chem. Bcr. 96, 639 (1963).
[3] E. Hecker and E. M e p r , Chem. Ber., in the press.
Thermal Dehydrogenation of
By Dr. A. Jankowski and Dr. S. R. Paulsen
Bergbau-Forschung GmbH., Forschungsinstitut des
Steinkohlenbergbauvereins, Essen-Kray (Germany)
Rearrangements of p-Quinols in
Trifluoroacetic Anhydride
By Doz. Dr. E. Hecker and E. Meyer
Max-Planck-lnstitut fur Biochemie, Miinchen (Germany)
C,C-Dialkyldiazacyclopropanes ( I ) are dehydrogenated by
oxidizing agents (yellow mercuric oxide, permanganate,
chromic acid) to give C,C-dialkyldiazacyclopropenes (2)
p-Alkylphenols of biochemical importance are oxidized
during intermediary metabolism to p-quinols [I], which
rearrange to alkylhydroquinones under the influence of
Angcw. Cliein. interiiat. Edit.
Vol. 3 (1964) / No. 3
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cyclodecapentaenes, system
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