The di- and trichloroacetyl isocyanates react with dimethyl sulfoxide (DMSO) to give substituted sulfylimines, the formation of which proceeds through a ...
REACTION
OF ACYL
DIMETHYL
SULFOXIDE
ISOCYANATES
]3. A . A r b u z o v , N. N. a n d O. V . S o f r o n o v a
WITH
UDC 542.91:547.239.2:547.269
Zobova,
The di- and t r i c h l o r o a c e t y l i s o c y a n a t e s r e a c t with dimethyl sulfoxide (DMSO) to give substituted sulfylimines, the f o r m a t i o n of which p r o c e e d s through a 4 - m e m b e r e d c y c l i c compound [1]. It seemed of i n t e r e s t to study the r e a c t i o n of the benzoyl (I) and t r i f l u o r o a c e t y l (II) i s o c y a n a t e s with DMSO. T r i f l u o r o a c e t y l i s o c y a n a t e riD, as a s t r o n g e l e c t r o p h i l e , r e a c t s with DMSO the s a m e as do the diand t r i c h l o r o a c e t y l i s o c y a n a t e s to give N - t r i f l u o r o a c e t y l - S , S-dimethylsulfylimine (IiI):
CF~C--N=C=O ii
0 (II) + (CH~)..S=O
FCF3CO--N--C=O7 ~I
,
|
i
I
CH,~
tJ
s-o I\
I
L
I]zC
CH~
l _~TCF3CON=S
/ \
(HI) CH3
CF3CONH2 + (CHs)~S=O
P20~ I
--H~O
The s t r u c t u r e of (III) was established via the e l e m e n t a l a n a l y s i s data, IR s p e c t r u m , and independent s y n t h e s i s f r o m t r i f l u o r o a c e t a m i d e and DMSO in the p r e s e n c e of P205 by analogy with [2]. The IiR s p e c t r u m of (III) has the absorption bands of v C = 0 1740, v S = N 965 cm -I (in h a r m o n y with the data given in [3]), v ~ _ F 1320, V~SF 1150 and 1170 cm -1. The r e a c t i o n of (I) with DMSO gave a somewhat unexpected r e s u l t . The sulfylimine was not obtained. A p p a r e n t l y , the r e a c t i o n does not proceed on the type of [Tr2 + ~2]-cycloaddition, but r a t h e r on the ~r of iv 2 + 7r4]-cycloaddition to give 2, 2 - d i m e t h y l - 6 - p h e n y l - 4 - o x o - 5 , 6 - d e h y d r o - 1 , 2 , 3, 5-dioxathiazine (IV). C6H,~
\/\
cH~
O
/
CH~
s CoHsC--N ==C=O +" 0 =S ri
0
\
'~
N
CH3
~/ o (iv) The s t r u c t u r e of (IV) was c o n f i r m e d by the e l e m e n t a l a n a l y s i s and IR s p e c t r a l data: v C = O 1738, v c = N 1615 cm J . EXPERIMENTAL
METHOD
The IR s p e c t r a w e r e taken inNu)ol on a UR-20 i n s t r u m e n t . The D M S O w a s purified by keeping o v e r Call 2 for a long t i m e and v a c u u m - d i s t i l l a t i o n o v e r Call2; we used f r e s h l y distilled DMSO. N - T r i f l u o r o a c e t y l - S , S - d i m e t h y l s u l f y l i m i n e (III). a) To a solution of 0.5 g of (II) in 30 m[ of absolute CHC13 was added 0.3 g of DMSO in d r o p s . After 2 h the CHCI 3 was r e m o v e d in vacuo and the r e sidue was distilled, bp 62 ~ (2 ram); n~ 1.4004; d 25 1.3355; yield 0.38 g (60%). Found: C 27.40; H 3.54; N 18.25%. C5H603NSF 3. Calculated: C 27.75; H 3.47; N 18.50%. b) To a solution of 5.6 g of t r i f l u o r o a c e t a m i d e in 40 ml of CHCI3, w e r e added 1 g of P205 and 3.9 g of DMSO. The m i x t u r e was refluxed for 30 min, cooled, another 1 g of P205 was added, and the m i x t u r e was again refluxed for 30 min. After cooling, the m e t a p h o s p h o r i c acid was s e p a r a t e d by decantation, the V. I. U l ' y a n o v - L e n i n Kazan State University. T r a n s l a t e d f r o m I z v e s t i y a Akademii Nauk SSSt~, Seriya K h i m i c h e s k a y a , No. 5, pp. 1206-1207, May, 1975. Original article submitted October 28, 1974.
9 19 75 Plenum Publishing Corporation, 22 7 West 17th Street, New York, N. Y. 100t 1. No part o f this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, microfilming, recording or otherwise, without writte;z permission n f the publisher. A copy o f this article is available from the publisher for $15.00.
1113
CHCI:~ was removed in vacuo, and the residue was distilled, bp 62 ~ (2 ram); n~ 1.4004; d 25 1.3355; yield 2.3 g (50%). The elemental analysis data show satisfactory a g r e e m e n t with the calculated values. 2, 2 v D i m e t h y l - 6 - p h e n y l - 4 - o x o - 5 , 6 - d e h y d r o - 1 , 2 , 3, 5-dioxathiaziae (IV). To 2.3 g of (I) was added 1.2 g of DMSO, and then 1 drop of BF 3 e t h e r a t e was added. C r y s t a l s deposited after 2 h, which were filtered and washed with absolute e t h e r , mp 155~ yield 2.76 g (80~). Found: C 53.28; H 4.72; S 14.18%. C10HlIO3NS. Calculated C 53.33; H 4.88; S 14.2Z~. CONCLUSIONS Trifluoroacetyl isocyanate reacts with DMSO to give the substituted sulfylimine, while benzoyl isoeyanate reacts to give the dioxathiazine derivative. LITERATURE 1. 2. 3.
1114
CITED
R. Neidlein and E. Heukelback, Arch. P h a r m . , 2--99, 64 (1966). G. Melloni and G. 1VIodena, Internal. J. Sulfur C h e m . , A_.~I, No. 2, 126 (1971). Yu. A. Nuzhdina, Yu. P. Egorov, G. S. Fedyuk, and L. P. Markovskli, T e o r . i ~:ksperim. K h i m . , 10, 393 (1974).
