close

Вход

Забыли?

вход по аккаунту

?

An e-Lactam Derived from 2-Adamantylamine.

код для вставкиСкачать
radical (2) rapidly undergoes the reverse reaction ( k - ') or
elimination ( k 2 )to give pentacoordinated[61N-stannyltriazene (3). In any case, no stabilization products ( 4 ) , which
could be formed from (2) through H-abstraction from the
powerful radical scavenger present (organotin hydride),
were detected. Attack on NZwould lead to the intermediate
It may be assumed that attack of the 7~ system of the azo
group also occurs as a competing reaction in the case of
eq. (1)but remains very much in the background owing to
a lack of readily replaceable groups R. This behavior of
the N-N group would correspond to that of internal
c=C groups"'.
The reactions depicted in eq. (1) and eq. (2) are greatly
accelerated, or in some cases even made possible, at 80°C
by free radicals from azoisobutyronitrile or at 28°C by
UV irradiation (h,,, 254 nm).
R'TR~
N - SnR3
I
Ar-N.
(5)
radical ( 5 ) , but no reaction products of this species were
observed.
Initial attack by the stannyl radical on N3 with subsequent
1,l-displacement of R' (SH2a)can also be ruled out since
The triazene system behaves here as a triaza analog of the
allyl system and it is likely that the S,2y reaction described
above is possible with all allyl analogs, as we have actually
observed with the allyl system itself[*].A number of allyl
displacement reactions proceed by the same mechanistic
route['', while various other free radical reactions''']
correspond to an SH2pmechanism.
Received: July 16,1971 [Z 478 I€]
German version: Angew. Chem. 83,850 (1971)
Table. S,2u and S,2y reactions of aryltriazenes (1) (0.4 M in cumene
at 80°C) with (C,H,),SnH. molar ratio 1 :4. Results after six hours'
reaction. Catalyst : azoisobutyronitrile.
(1)
Ar
R'
R2
Yield (mol.-%)
based on
reacted (I)
Ar-H
R1-H
eq. (1)
eq. (2)
100
100
100
13
10
7
7 [c]
2
61
0
0
0
a7
90
al;{7,
93
98 [a1
re1
An a-Lactam Derived from 2-Adamantylaminet**I
By Erach R . Talaty,James P. Madden, and Louis H . Stekol"']
Several a-lactams having a tertiary-alkyl group attached
to the nitrogen atom are known['! Attempts to prepare
a-lactams with other types of alkyl substituents on nitrogen
have been made, but such a-lactams have been reported
to be either not formed or too reactive to be isolated['!
We now report the isolation of an a-lactam, 1-(2-adaman-
[a] R'-H is in equilibrium with ( I f ) or ( I h ) respectively
[b] At 60°C without catalyst.
[c] Benzene (Ar-H) is formed here from spontaneous decomposition
of (IS).
[d] In toluene at 20°C without catalyst.
[el NH, is formed. A quantitative determination has yet to be performed.
benzylaniline, diphenylbenzylamine, or N-benzylimidazole
gives no toluene under the above conditions. Moreover,
such an attack is unlikely in the case of the triphenylmethyl
derivative ( I g) for steric reasons.
[l] J . Hollaender, Dissertation, Universitat Dortmund 1971.
[2] W P. Neumann and Hch. Lind, Chem. Ber. 101,2837 (1968).
[3] K . Riibsnmen, W P. Neumann, Ra. Sommer, and U . Frommer,
Chem. Ber. 102, 1290 (1969), and earlier literature cited therein.
[4] W P. Neumann, Hch. Lind, and G. Alester, Chem. Ber. 101, 2845
(1968).
[S] For a review, see A . G. Dacies and B. P. Roberts, Nature Phys.
Science 299, 221 (1971).
[6] F. E. Brinckmann, H . S . Haiss, and R . A . Robb, Inorg. Chem. 4,935
(1965); see also ref. [I].
[7] R . Sommer and H . G. Kuicila, J. Org. Chem. 33, 802 (1968); H.-J.
Albert, W P. Neumann, W. Kaiser, and H:P. Ritter, Chem. Ber. 103,
1372 (1970), and further literature cited therein.
[S] H:J. Alberr, W. P . Neumann, and H.-P. Rirrer, Liebigs Ann. Chem.
737, 152 (1970).
191 R . K h . Freidlina, Advan. Free Radical Chem. I , 211 (1965), and
further literature cited therein.
[lo] J . K . Kochi and P. J . Krusic, J. Amer. Chem. SOC.91,3944 (1969),
and further literature cited therein.
Angew. Chem. internat. Edit.j Vol. 10 (1971) / No. 10
R1-CHR2-CO-R3
( a ) , R 1 = I-adamantyl,
( b ) . R' = I-adamantyl,
(c), R' = 1-adamantyl,
(1)
R 2 = H, R3 = C1
R2 = Br, R3 = CI
R2 = Br, R3 = NH-2-adamantyl
tyl)-3-(l-adamantyl)aziridin-2-one( 2 a ) , which has a secondary-alkyl group attached to position 1, and is remarkably stable. Compounds of this type could also have potential
applications in medicinal chemistry, since l-adamantylamine and its derivatives have been reported to have antiviral activityf31.
The acid chloride ( l a ) was treated with bromine in boiling
carbon tetrachloride until conversion into ( I b ) was
complete, and the crude reaction mixture was allowed to
react with 2-adamantylamine to afford, in 71 % over-all
yield, the bromo-amide ( I c ) , m. p. 237.5-24O.O"C (decamp.) [NMR (CDCl,, 60MHz, &value in ppm relative
to TMS): 6.60 (N-H/broad d, J = 8 Hz), 4.08 (1 H/s),
4.08 (1 H/broad d, J = 8 Hz), 2.26-1.44 (29 H/m); mass
spectrum: m/e 407/405 (M+), 326 (M'-Br)].
Reaction of
(Ic) with potassium tert-butoxide in ether at 0°C effected
ring closure to the desired a-lactam (2a), m.p. ~ 2 2 5 ° C
(decomp.). However, in contrast with the preparation of
a-lactams such as (Zb)[41, where the ring-closure could be
[*I
Prof. Dr. E. R. Talaty, J. P. Madden, and L. H. Stekoll
Department of Chemistry, Wichita State University,
Wichita, Kansas 67208 (USA)
This work wassupported by the Wichita State University Research
Committee.
[**I
753
driven to completion by the use of an excess of base without
the concomitant formation of other products, the present
reaction required very careful control of the reagents and
experimental conditions in order to achieve optimum conversions. The isolation of (2a) was accomplished only after
fractional crystallization at low temperatures. The structure of (2a) is supported by spectral data [IR (CCl,):
v=1850cm-'; NMR (CDCI,, 60MHz, &-value in ppm
relative to TMS): 2.53 (H3/s),3.16 (1 H/broad s),ca. 2.4-1.4
(29 H/m); mass spectrum: m/e 325 (M')].
under the same conditions requires 3.5 h. The chemical
stability of (2a) is equally remarkable: its complete decomposition in boiling methanol at a concentration of
1.5 mmol/lO ml occurs only after 1.75 h. By comparison,
(26) requires 30 h for complete decomposition under
identical conditions, and ( 2 c ) is reported to decompose in
methanol at 5°C within 20 minutes''! Thus, the stability
of (2a) is superior to that of ( 2 ~ ) and
' ~ approaches
~
that
of (2d), the most stable class of a-lactams known so far.
Received: July 5,1971 [Z 471 IE]
German version: Angew. Chem. 83,848 (1971)
:I1wo
N
(2)
(a), R i = 1-adamantyl, R 2 = 2-adamantyl
fb), R i
fC), R'
( d ) , R'
=
=
=
R2 = 1-adamantyl
C,H5, R 2 = C(CH,),
R2 = tert-alkyl
The thermal stability of the novel a-lactam (2a) is illustrated by the observation that its complete decomposition in
boiling xylene (138°C) at a concentration of 0.4 mmol/6 ml
requires 1 h, whereas the complete decomposition of (2b)
[I] See E. R. Talaty and C. M . Utermoehfen,Tetrahedron Lctt. 1970,
3321, and references cited there; J . C. Sheehan and M . M . Nafssi-K
J. Org. Chem. 35, 4246 (1970); S. Sarei, B. A. Weissman, and Y: Stein,
Tetrahedron Lett. 1971,373.
[2] I. Lengyef and J . C . Sheehan, Angew. Chem. 80.27 (1968); Angew.
Chem. internat. Edit. 7, 25 (1968).
[ 3 ] P. E. Afdrich, E. C . Hermann, W E. Meier, M . Paulshock, W W.
Prichard, J . A. Snyder, and J . C. Watts, J. Med. Chem. 14, 535 (1971).
[4] E. R . Tafaty, A. E. Dupuy, Jr., and A. E. Cancienne, Jr., J. Heterocyclic Chem. 4, 657 (1967).
[5] H. E. Baumgarten, R . L. Zey, and U . Krolls, J. Amer. Chem. SOC.83,
4469 (1961).
[6] The published data on the thermal stability of (2c)-appreciable
decomposition at 105°C-do not allow an accurate comparison with
( 2 a ) and (2b); J . J . Fuerholzer, Ph. D. dissertation, University of
Nebraska, 1965.
CONFERENCE REPORTS
Reactions of Adamantanes and Their Derivatives
in Sulfuric Acid
By J . Schiatmann'"]
Under suitabie conditions I-adamantanol can be converted
into adamantanone in concentrated sulfuric acid. The key
reaction is the reversible isomerization of 1- to 2-adamantanol; the equilibrium is much in favor of the I-isomer. It
has been proved that this isomerization occurs intermolecularly. The 2-adamantanol present in the reaction mixture
is transformed into adamantanone by a hydride shift, the
hydride acceptor being either the adamantanyl cation
(yielding adamantane as a by-product) or the sulfuric acid.
Adamantane is reconverted into I-adamantanol by sulfuric
acid; thus the synthesis of adamantanone can also be
carried out from adamantane (yield ca. 50%).
Besides adamantanone, adamantanediols are formed from
I-adamantanol in sulfuric acid, presumably also in hydride
shift reactions, with either the adamantanyl cation or the
sulfuric acid as hydride acceptor. Although these are
unimportant side products when the reactions are performed in concentrated sulfuric acid, conditions can be
p] Dr. J. Schlatmann
N. V. Philips-Duphar
Weesp (Holland)
754
found in which the diol formation will be enhanced and the
adamantanone formation suppressed because all these
reactions are influenced differently by the concentration
of the sulfuric acid. Thus in 20% fuming sulfuric acid the
formation of the 1,3-, 1,4- and 2,6-adamantanediols predominates. After oxidation with chromic acid the components of the reaction mixture can be separated and 5hydroxyadamantanone (yield ca. 50%) and 2,6-adamantanedione can be isolated in pure form.
Lecture at Aachen on May 25,1971 [VB 309 IE]
German version: Angew. Chem. 83, 732 (1971)
Mechanism of Cyanation of Tertiary Amines['*]
By Gabor Fodor and Shiow-yueh Abidi"]
We have been able to show that the von Braun cyanogen
bromide degradation of tertiary amines proceeds by two
successive steps :
[*I
Prof. Dr. G. Fodor and Dr. Sh. Abidi
West Virginia University
Department of Chemistry
Morgantown, West Virginia 26506 (USA)
[**I This work is being supported by National Science Foundation,
Grant GP-26558.
Angew. Chem. internat. Edit. / Vol. 10 (1971)
/ No. 10
Документ
Категория
Без категории
Просмотров
1
Размер файла
207 Кб
Теги
lactam, adamantylamine, derived
1/--страниц
Пожаловаться на содержимое документа