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Vinylogous Pyridinecarbaldehydes by Wittig Reaction.

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are dried in an oil-pump vacuum. Yield 6.2g (65% based
on the stoichiometry given in ref.[51).
Received: March 10. 1975:
supplemented: March 17. 1975 [Z 217 IE]
German version: Angew. Chem. 87.485 (1975)
All three isomeric aldehydes ( 1 ) can be obtained more
conveniently and in improved yields by Wittig
The reactions leading to the phosphorane (2) are described
in the
Cf. H . G . Heal, Adv. Inorg. Chem. Radiochem. 15. 375 (1972); H.
J. EmelPus. Endeavour 32. 76 (1973); H. W. Roesk!. Chem. Ztg. 98,
121 (1974).
While the existence of [SIN,]. hdS only been established below 0 ° C
[3]. that of [S4N4I4- has not been confirmed beyond doubt [4].
R . A. Meinzer, D. W Prarr, and R. J. M.vers. J. Am. Chem. SOC.
9 / , 6623 (1969).
A. J. Banister and D. Younger, J. Inorg. Nucl. Chem. 32, 3763 (1970);
M. Becke-Coehring and R. Schwarz. Z. Anorg. Allg. Chem. 296, 3 (1958).
The mass balance indicates the following overall equation:
I7(CHj)nCNSNH
[I21
[I31
[I41
[15]
-+
+
~ [ ( C H I ) ~ C N H ~ ] + [ S J N S ] -S[ICH.~)JCN]~S
~ICHJ~~CNH
NI?
+
+
lCH,,),CNSNH. which can readily be enriched in highly dilute solution.
can be detected by 'H-NMR spectroscopy.
Slow deposition of S4N4 from the solutions, which are always red
at high concentration 171, begins after several hours in methanol. So
far SIN4 is also the sole product isolated on thermolysis (decomposition
of ( 2 ) begins at about 70°C).
It remains t o he established whether radical species, e.g. [SNZ]: [S],
are also formed in the process.
I. Rupperr. !I Basrian. and R. Appel, Chem. Ber. 107, 3426 (1974).
We are grateful to Prof. Dr. W Beck. Munich, for carrying out the
measurement.
Supported by the alkaline hydrolysis of the two salts. which gives
no indication of a n N-N bond (hydrazine). A final decision can only
be based on an X-ray structure analysis to be performed by Prof. Dr.
J. Weiss, Heidelberg.
Just as S4N4andAs4SIreDresent a molecular pair with inverse structure,
[S4N5]-. which possesses the same number of electrons a s the still
unknown speciesSsN4, and As4Ss"" would be the second such example.
7: J. Basrow and H. J . Whitfield. J. Chem. SOC. Dalton Trans. 1973.
1740.
Cf. also the proposed structure for the hypothetical [S4N4lZ-: R.
Gkirer. J. Chem. SOC. Al970. 3174, and the structure of [S4NsO]-:
R. Strudel. P. Lugo.. and H. Bradricek. Angew. Chem. 85, 307 (1973):
Angew. Chem. internat. Edit. 12. 316 (1973).
Somewhat larger crystals are formed with no stirring: however. they
are sometimes orange-yellow in color.
These data should be viewed with reservation since the removal of
small amounts of substance from the frit with a spatula led t o a d e n t
explosion!
Pyridineacrylaldehyde (1)i'J
A mixture of freshly distilled pyridinecarbaldehyde (1.71 g;
15mmol) and (2) (4.90g; 16mmol) in anhydrous benzene
(100ml) is heated under reflux for 24h. The reaction is
preferably carried out under nitrogen; in the case of the 4isomers this is essenti?l. After removal of solvent the solidified
residue is extracted with ice-cooled ether; (C6Hs)3F'=0 remains behind. The extract is concentrated and the resulting
brown oil vacuum-sublimed in a small apparatus (oil pump). At
first unreacted pyridinecarbaldehyde condenses on the cool
finger; this is followed, at higher temperatures, by sublimation
of the reaction product [2-(1) and 4-(1) at 60°C/0.3 torr,
3-(1) at 8O0C/O.3 torr]. Yields: 2 4 1 ) 21 %, 3-(1) 56%, and
4-(1) 62%; m.p.: 2-(1) 39--40°C (43"Cr']), 3-(1/ 65-66°C
(66-67°C14') and 4-(1) 35-36°C (36-37 TI4]), all from
petroleum ether; semicarbazone of 4-(1) 21 1.5"C, phenylhydrazone of 4-(1) 199"C, both from ethanol/water; oxime of
4-( 1) 148- 1 50 "C, from benzene.
Received: March 3, 1975;
supplemented: April 1, 1975 [Z 224 IE]
German version: Angew. Chem. 87.486 (1975)
CAS Registry numbers:
2-I I )a 516x9-49-7: 3-( I ). 28447-15-6: 4-(1). 26505-:6-2:
(2). 2136-75-6: 2-pyridinecarbaldehyde. 1121-60-4:
3-pyrridinecarbaldehyde. 500-22 1 ; 4-pyridinecarbaldehyde. 872-85-5
[I]
M . Ohra and Y Isowa. Nippon Kagaku Zasshi 80. 688, 1198 (1959):
Chem. Abstr. 55, 3635a. 4505a (1961).
M. Strell and E . Kopp, Chem. Ber. 91, 2854 11958).
G. B. Ellam and C. D. Johnson, J. Org. Chem. 36. 2284 (1971).
L. S. Dallies and G. Jones. I. Chem. SOC.1971.2572.
S. Trippert. Quart Rev. Chem. SOC. 17, 406 (1963).
S. Eipperr and D. M. Walker. J. Chem. SOC.1961. 1266.
W Hohler, Dissertation, Universitat Freiburg 1973.
Vinylogous Pyridinecarbddehydes by Wittig Reaction
[2]
[3]
141
[S]
[6]
[7]
By Ilse Hagedorn and Wolfram Hohler"]
Condensation of aromatic aldehydes of the pyridine series
with acetaldehyde leads to only very small yields of the pyridineacrylaldehydes ( 1 ).
1,2,3-Tri-rert-butyldiazaphosphiridine3-Oxide['**l
By Helmut Quast, Manfred Heuschmann, and Mohamed 0 .
Abdel-Rahman[*]
The chemistry of three-mem bered phosphorus heterocycles
is still underdeveloped in comparison with that of the analo-
According to a Japanese report['] 2-( I ) can be prepared
in 44% yield with the aid of Amberlite I R 4 B ; however,
on trying out this procedure only 10% was obtained141.3-(1)
is also formed by decarboxylation of P-picolylidenepyruvic
acid (4.5 %)r2J. Hydrolysis of the corresponding substituted
tetrahydro-1.3-oxazine affords 14% 3-(/) or 23% 4-(l)I4].
[*I
Prof. Dr. I. Hagedorn and Dr. W. Hohler
Chemisches Laboratorium der Universitat
78 Freiburg. Albertstrasse 2 I (Germany)
486
[*] Doz. Dr. H. Quast [+I. Dipl.-Chem. M. Heuschniann. and Dr. M. 0.
Abdel-Rahman [**I
lnstitut fur Organische Chemie der Universitat
87 Wurzburg, Am Hubland (Germany)
[ +] T o whom correspondence should be addressed.
[**I Present address: National Research Centre, Dokki. Cairo (Egypt)
["'I Three-Membered Heterocycles, Part 3. This work was supported by
the Fondsder Chemischen Industrie. M. 0. A.-R. IS indebted to the Alexander
von Humboldt-Stiftung for a research grant (1970-1972). The results are
largely taken from the Diplomarbeit of M. H . Universitat Wurzburg 1974.
Part 2: H. Quasr and F. Kees, Angew. Chern. 86, 816 (1974): Angew. Chem.
internat. Edit. 13. 742 (1974).
Angea.. Chem. inrernat.
EJir. 1 Vol. 14 ( lY7.5) I No. 7
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