close

Вход

Забыли?

вход по аккаунту

?

Convenient General Synthesis of Alkinylcyclopropanes.

код для вставкиСкачать
t a l c , an C F -
.i
iancien ( v q l . / 2 / ) spielen keine Xolle.
/ 7 / G l e i r h L e i i I ; Luedinyt die Koordlnation des Pyridlns die
1 .~'~q~:dcutete
Reorientierung des nichtbindenden
in 'ilib.
MOs
/8/
z.B.
I!.-t3.Biirqi,
Che:h.lpt.[:<>s&
A s w e found r e c e n t l y , t h e eajily a c c e s s i b l e
1I 5 1
(tr i chlorov i nyl ) cyc 1 o pr o p a n e s
?,~r:!,.
vgl.
Dreparative methods, except for the reaction o' cyclopropanonhemiacetdl with alkinyl Grionard reaqentslll.
Angew.Chem.
14 (19751.
87
(19751,
460:
AnSew.
re a c t w i t h
2 moles o f n-butyllithium in etlierlhexane at -73'C
1 1 t h i um
(1-chlorocyclopropy1)-substituted
461.
l-chloro-l-
c 1 ed n 1 y
t o qive
ace'yl i d e s 6.
These can be solvolyzed by methanol o r water t o yield ( 1 Elncjeganqen am 4.
Juni 1 9 8 1
9 6 5 S/
/Z
c h l o r o c y c l o p r o p y 1 ) a c e t y l e n e s 7 (see T a b l e
3r trapped
1)
with a wide variety o f electrophiles t o give hiqh y i e l d s of
the corresponding acetylene derivatives 5 (see Table 2 ) .
Table 1 .
(1-ChlorocyClopropy1)acetylenes
7 from l-chloro-
l - ( t ~ i C h l O ~ O v i n y l ) C y C l O p r O D a ~ e1 S/ 6 1 .
Vinylcyclopropane 1
R1
Rz
R3
CycloproDylacetylene 7
Yield [ % I
R4
(Isolation'b])
[a] Mixture o f stereoisomers. [bl A: Shortpath desti1Idtion,
8 : Prep . g a s c h r om at o g ra p liy
-
33 -
-
35 -
This type o f reaction corresponds t o the principal scheme of
Dieses Manuskript ist
zu zitieren als
Angew. Chem. Suppl.
This manuscript is
to be cited as
Angew. Chem. Suppl.
1982,34-40
1982,34-40
reactions o f 1,l-dichloroethylenes with a l k y l l i t h i u m c o m pounds a s established by Kobrich e t a1./6/
chlorine metal exchange t o yield t h e s t e r e o i s o m e r i c
0 Verlag Chemie GmbH, D-6940 Weinhelm. 1982
0721 4227/82/01010034S02.50/0
rapid
car-
benoids ( € 1 - 2 and ( 2 ) - 2 . S u b s e q u e n t p - e l i m i n a t i o n o r
Fritsch-Butenberg-Wiechell
rearrancemfvt/7/ t h e n f o r m s t h e
Alkinylcyclopro-
C o n v e n i e n t G e n e r a l S y n t h e s i s of
panes
(see s c h e m e 1 ) .
Thereby the trichlorovinyl derivatives 1 undergo a
chloroacetylenes 4 % which further react with b u t y l l i t h i u m
t*
to yield the lithium acetylides 6 . With less than 2 moles
By Thomas Liese and Armin d e Meijere
'
R'
R'
Dedicated to Professor Oskar Glemser on t h e occasion o f h i i
R'
70th birthday
3
Meanwhile donor-Ill and acceptor-substituted/2/
cyclopro-
-
'R
panes a s we1 I as vinylcyclopropanes/3/ have become e s t a b -
1
lished tools o f t h e synthetically oriented organic chemist.
Althouah the combination o f a cyclopronyl and an
fast
alkinyl
group offers an interestins and powerful synthetic o s t e n -
;&
RR4
y
(2)-2
\
4
'cl
tial. alkiiylcyclopropanes hdve not been recocniied wid?ly.
[*I
the
Prof. D r . A. de Meijere. Dip].-Chem.
lack of
R'
R'
R'
The reason f o r this may have b e e n
aeneral
Th. Liese. Insti-
tut fur Orqanische Chemie und Biochemie d e r Universit a t . Martin-Luther-King-Plat2 6 , D - E O G O Hamburg 13.
5
€
6
7
L'
"
[ * * I This work w a s supported by t h e Fonds der Chemischen
Scheme 1.
(a) n-BuLi, Et*O/hexane, -78°C;
(b)
lndustrie and t h e Hoechst AG.
-78OC; (c) E X . -20 t o O°C, 1-4 h ; (d) MeOH, r.t.
-
34 -
-
36 -
MeOH, T H F ,
of butyllithium the chloroacetylenes 1 a n d , a f t e r h y d r o -
R e f e r e n c e s and f o o t n o t e s .
lysis, small fractions ( 5 5 % ) o f the ( E l - ( d i c h l o r o v i n y l l -
12 (1980), 2 7
/1/ E.Henkert, ACC. Chem. Res.
cyclopropanes 3 can be isolated. The latter proaucts occur
and ref. cited
there1 n.
by trapping of t h e (E)-configurateo carbenoids (El-2,which
are kinetically hindered / 6 /
/ 2 / Cf. S.Danishefsky.
in t h e i r
(1979), 66 and
Acc. Chem. Res.
further reaction
ref. cited t h e r e i n ; R.V.Stevens, P u r e Appl. Chem.
relative t o (Z)-2.
(1979), 1317 and ref. cited therein.
Table 2 .
(l-Chloro-2.2,3,3-tetramethylcyclopropyl)acetylene
derivatives 5 1 from l - c h l a r o - 2 . 2 , 3 , 3 - t e t r a m e t h y I
/3/ Cf. J.M.Conia,
- 1 - ( tri -
c h l o r o v i n y 1 ) c y c l o p r o p a n e l a 181.
E
Mp. ["CI
[moll
ibld.
98 (1976), 248 and ref. cited therein; H.H.Wasserman,
Products
Excess
3 1 7 and ref.
M.J.Boadanowlcz, J. Am. Chem.
_
SOC.
_ -9 5 (1973), 2 8 9 , 5 3 1 1 ; B.M.Trost, D.E.Keeley.
Reagents
EX
43 (1975).
Pure Appl. Chgm,
cited therein; 8.M.Trost.
Yield
[%I
R.E.Cochoy.
M.S.Baird,
ibid. 91 (1959), 2375 and ref
cited therein
(Isolation[aJ)
/4/ J.Salaun. F.Bennani, J.-C.Compain, A.Fadel. J.OIIivier,
-[bl
J . Orq. Chem,
5
45
(1980). 4129 and ref. cited therein.
/5/ W.Weber, A.de Meiiere, Angew. Chem.
1.1
Angew. Chem. Int. Ed. Enql.
2.5
19
92
(1980), 135;
(19801, 138; W.Weber.
Dissertation, Univ. Gottingen, 1900.
1.1
161 a ) G.Kobrich, Angew. Chem.
1.1
Int. Ed. Engl.
4
Chem. Ber.
1o[cJ
84
(19721, 5 5 7 ; Anqew. Chem.
11 (1972), 4 7 3 ;
2 (19661, 1773
b) G.Kobrich, K.Flory,
and ref. cited therein.
/ ? / Cf. V.Jager in Houben-Weyl-Muller, Methoden d e r Orga:
8
nischen Chemie, Thieme Verlaq, Stuttqart 1977. Vol. V2a,
6.5
p. 214 ff.
10
181 All new compounds were fully characterized by 'H-nmr
[a]
n:
A: recrystallisation, 8 : distillation, C: sublimation,
column chromatography. [bl Gaseous Co2 introduced.
[cl Addition o f 30 mol % HMPA necessary.
-
37 -
The 1-chloro-1-alkinylcyclopropanes
-
spectra and in addition by e i t h e r some o r all of 13C-
5 and 7 r e s p e c t i v e l y
nmr-, IR-, mass spectra and elemental analysis.
are polyfunctional molecules and a s such valuable building
blocks f o r organic synthesis. Amonq t h e reactions which can
be performed with them are t h e exchanqe o f chlorine with
39 -
/9/
Th.Liese, A.de Meijere. unpublished results; Th.Liese,
part o f t h e forthcoming dissertation, Univ. Hamburq.
other substituents (via lithiation of 6 ( E = SiMe3) a n d
consecutive electrophilic substitution), the rinq o p e n i n g
Received: June 29,
t o enines (with Lewis acids),
the transforrxation t o cyclo-
propyl ketones ( b y mercuric salt catalyzed hydratization)
and cyclopropane carboxylic acids (by ozonation)/9/.
General procedure: 4. t mmol n-butyllithium (1.9 M solution
in hexane) are added dropwise with a syrinqe t o a stirred
solution of 2 mmol II in 10 ml dry e t h e r kept a t -78'C
and
under nitrogen. (With larger batches t h e precooled (-40°C)
butyllithium solution is added through a coolable dropping
funnel). T h e mixture is stirred at -78OC for a n additional
15
-
30 min, then t h e cooling bath is removed and t h e neat
electrophile ( s e e Table 2 ) i s added during t h e warminq-up
period at - 2 0 t o O°C.
for 1
-
After stirring at r o o m temperature
4 h t h e reaction mixture i s added t o a n ice-cooled
saturated solution of ammonium chloride. The orqanic layer
1s
separated and the aqueous o h a s e extracted with e t h e r .
The combined organic s o l u t i o ~ s are dried over m a q n e s i u m
sulfate, the solvent distilled over a short column a n d the
residue shortpath-distilled into a cold t r a p (isolation see
Tables 1 and 2 ) .
-
38 -
- 40 -
1981
/Z
963 S/
Документ
Категория
Без категории
Просмотров
1
Размер файла
132 Кб
Теги
synthesis, general, convenient, alkinylcyclopropanes
1/--страниц
Пожаловаться на содержимое документа