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Cyanation of Tertiary Alkyl Chlorides A Novel Method for the Geminal Dialkylation of Ketones.

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[ I ] a) E. JZgers, W.Steglich. Liebigs Ann. Chem., in press. b) W.Steglich. W.
Furtner. A. Prox. Z. Naturforsch. 8 2 5 . 557 (1970).
121 G . Pattenden. Fortschr. Chem. Org. Naturst. 35. 133 (1978).
[3] (2a): M.p.=28O0C (decomp.); UV (MeOH): L,,,=272 (Ig&=4.10), 290
(4.04), 360 (4.04). 450 nm (4.12); IR (KBr): 1785, 1745, 1650, 1629 c m - ' ;
'H-NMR ([D6]DMSO): 6 = 5.85, 6.65, 7.25 (each s, 3 H), 10.25 (br., OH);
MS: m / r 262 (75%. M + , Ci2H6O7),192 (100, CUH,05); (3): L , = 2 6 9
(Igs=3.99), 288 (4.02). 361 (4.15). 450 (3.73).
[4] Cf. H. Endres. 2. Anal. Chem. 181,331 (1961).
[5] T. Posternak. R. G. Huguenin. W. Alcalay. Helv. Chim. Acta 39. 1564
(1956). Rearrangement of the dibenzoquinones was performed under
conditions of acid catalysis.
[6] Cf. e . g . H. W. Moore. R . J. Wickholm in S. Patai: The Chemistry of Quinonoid Compounds, Part 1, Wiley, London 1974.
[7] C . G. Swain. J. F. Brown. Jr., J. Am. Chem. SOC. 74, 2538 (1952); H . C.
Beyerman. W . M . van den Brink. Proc. Chem. SOC.1963.266; H . T. Openshow. N. Whittaker, J. Chem. SOC.C 1969, 89.
[8] P. C. Beaumont. R . L. Edwards. J. Chem. SOC. C 1969. 2398.
191 Reaction time and yield apply to synthetic (16) with a sterically nonuniform side chain. Interestingly, natural boviquinone-4 with a n all-(Q-geranylgeranyl side chain is dimerized much more slowly by polyamide.
Dimeric N-Chloroiminosulfur Tetrafluoride,
a Cyclodiaza-k6-thiane with Hexacoordinated
Sulfur[**]
By Alfred Waterfeld and Riidiger Mews[']
Dedicated to Professor Oskar Glemser on the occasion
of his 70th birthday
The previously known cyclodiaza-h6-thianes"1 contain
exclusively tetracoordinated sulfur atoms. However, by
reacting NSF, and CIF we were able to isolate the novel
cyclodiaza-h6-thiane (I) with hexacoordinated sulfur
atoms, in addition to the previously described product of
this reaction, N,N-dichloroaminosulfur pentafluoride
(2)[2'.
K S F 3 + C1E'
CIF
{C1N=SF4)
I
Cl,N-SF,
12)
c1
C1
Whether the four-membered heterocycle is formed by
direct dimerization of the N-chloroaminosulfur tetrafluoride or via ionic intermediates is still at present not clear.
N-alkylaminosulfur tetrafluorides, such as e. g . CH,NSF,,
do not dirnerize"].
The colorless compound (I) melts at 4"C, and its vapor
pressure at 20 " C is 7 torr. Whereas (I) decomposes in glass
vessels at room temperature, it appears to be stable in passivated metal flasks.
(I) was characterized by elemental analysis and spectroscopic methods. Apart from the molecular ion at m / z 314
(36%), the EI mass spectrum (70 eV, cold source) shows
peaks from the fragments (M-CIF)* 260 (20), CINSF:
157 (85), CINSF: 138 /34), SF: 127 (40), NSF: 103 (12),
SF: 89 (100). In the FI mass spectrum, a peak for
(M-CIF)+ was found in addition to that of M + . The IR
and Raman spectra exhibit no coincidences[41,and hence
1'1 Prof. Dr. R. Mews, Dr. A. Waterfeld
p
'
]
Anorganisch-chemisches lnstitut der Universitat
Tammannstrasse 4, D-3400 GBttingen (Germany)
This work was supported by the Deutsche Forschungsgemeinschaft.
Angew. Chem. Int Ed. Engl. 20 (1981) No. 12
the molecule is probably centrosymmetric with a transorientation of the two chlorine atoms. The NMR data can
be interpreted using an A2B2 system as a simplification:
6(F,)=76.1, 6(FB)=49.4, J(AB)= 140.8 Hz.
Procedure
CIF (22.9 g, 0.42 mol) and NSF, (21.8 g, 0.212 mol) are
condensed into a Monel cylinder at - 196°C. The reaction
mixture is slowly warmed up to - 78 " C ,and then to room
temperature (Care! Warming too rapidly leads to violent
explosions). Fractional condensation ( - 50, - 95,
- 196 "C) using an oil-pump vacuum yields (I) (1.2 g, 3.6%
yield) in the first cold trap and (2) (5.3 g, 1 1.8%)'21, together
with small amounts of impurities['], in the second.
Received: June 2, 1980 [Z 910 IE]
German version: Angew. Chem. 93, 1075 (1981)
CAS Registry numbers:
(1): 79593-52-5, (2): 22650-46-0, CIF: 7790-89-8, NSF,: 15930-75-3.
[ I ] K . D. Schmidt. R. Mews. 0. Glemser, Angew. Chem. 88, 646 (1976); Angew. Chem. Int. Ed. Engl. I S . 614 (1976); F. M. Tesky. R. Mews, B. Krebs.
ibid. 91. 231 (1979); 18. 235 (1979); H. W. Roesky. M.Aramaki. L. Schonfelder. Z . Naturforsch. 8 3 3 , I072 (1978).
121 A . F. Cli/ford, G. R. Zeilenga. Inorg. Chem. 8, 979 (1969).
[31 R. Mews. Angew. Chem. 90. 561 (1978); Angew. Chem. Int. Ed. Engl. 17.
539 (1978).
[4] Spectra were recorded in various phases [IR (gas): 970 (s), 930 (vw), 889
(vs), 854 (vw). 81 1 (s), 777 (m),617 (w). 578 (sh), 568 (m);Raman (liquid):
665 (m), 61 1 (w), 536 (w). 463 (w). 369 (vw), 350 ( s ) , 293 (w), 207 (w). 182
(w)l.
[5j SF,NSF, and (SF,),NH are more readily accessible by other routes (A.
Waterfed, R. Mews. unpublished results).
Cyanation of Tertiary Alkyl Chlorides:
A Novel Method for the Geminal Dialkylation of
Ketones[**I
By Manfred T. Reetz and Ioannis Chatziiosifidisl"
The ambidentate cyanide ions"' react with SN2-active
primary and secondary alkyl halides at the C atom to form
nitrilesf4] in accord with the Kornblum ruleL2]and the
HSAB principle[31.In the case of tertiary alkyl halides only
elimination of HX is observed"]. Under SN1 conditions, Nalkylation occurs via the Ritter reaction[61.In order to solve
the classic problem of the cyanation of tertiary alkyl halides [(1)+(3)], we reacted these with the readily accessible
trimethylsilyl cyanide[71(2) in the presence of catalytic
amounts of SnCI,.
R3C-C1 + (CH3)3SiCN
(1)
(2)
SKI,
R3C-CN
13)
+ (CH3)3SiC1
14)
As shown in Table 1, the desired tertiary nitriles are
readily obtained. Noteworthy is the CC coupling reaction of
exo-2-chloro-2-methylnorbornane(lj). which leads to the
exo-nitrile (3j) with 100% stereoselectivity. Furthermore,
the strict chemoselectivity in the reaction of (5) is notable:
the tertiary nitrile (6) is formed exclusively.
The present CC coupling reaction is of synthetic interest, because the products can be variously modified e. g . by
Grignard addition or reduction, leading to the otherwise
[*I Prof. Dr. M. T. Reetz, Dipl.-Chem. I. Chatziiosifidis
[**I
Fachbereich Chemie der Universitat
Hans-Meerwein-Strasse, D-3550Marburg (Germany)
This work was supported by the Fonds der Chemischen Industrie.
0 Verlag Chemie GmbH. 6940 Weinheim. 1981
0570-0833/81/1212-1017 S 02.50/0
1017
Table I. Cyanation of ferr-alkyl chlorides.
ferf-Alkylchloride
Nitrile
Yield [a]
“1
First Detection of a n-Coupled 1,s-Diradical
via CycloadditionI**]
By Gerd Kaupp and Inge Zimmermann[”
2-Chloro-2-methylpropane( l o )
2-Methyl-2-propacarboni- 75 (64)
trile (30)
2-Chloro-2-methylbutane (lb)
2-Methyl-2-butacarbonitrile80
(75)
(3b)
2-Methyl-2-heptacarboni- 78 (70)
trile (3c)
5-Chloro-5-methylundecane(Id)
5-Methyl-5-undecacarboni- 80 (70)
trile (3d)
1 -Chloro-1-methylcyclopentane ( l e ) I-Methylcyclopentacarbon-75 (67)
itrile (3e)
I-Chloro-l -ethylcyclopentane (11)
I-Ethylcyclopentacarboni- 87 (82)
trile (3fl
I -Chloro- I-methylcyclohexane ( l g j
I-Methylcyclohexacarboni-60 (38)
trile (39)
I-Chloro- 1methylcycloheptane (Ih) 1-MethyIcycloheptacarbon- 85 (76)
itrile (3h)
1 -Chloro-I -methylcyclododecane (1;) I-Methylcyclododecacar- 75 (60)
bonitrile (3;)
exo-2-Chloro-2-methylnorbornane (lj) exo-2-Methyl-2-norborna- 90 (84)
carbonitrile (3j)
2-Chloro-2-methylheptane (lc)
[a] The values reflect the ‘H-NMR spectroscopically estimated amounts; the
data in brackets are the yields of isolated products. The structures of all
products were confirmed analytically and spectroscopically.
not easily accessible neopentylamines. Since tertiary alkyl
halides are infer alia conventionally accessible from ketones, the cyanation also provides a novel method for geminal dialkylation of ket~nesI*.~’.
Diradicals such as ( I ) , (2). (3)11],
etc. establish a homologous series. This has to be differentiated from a homologous series of n-coupled diradicals (4)12’,(5)13],(6),etc. We
report on a cycloaddition of the first n-coupled 1,5-diradical. Thus, the formation and cycloaddition of (8) to a keto
group competes favorably with [2n 2x1-dimerizations of
electronically excited (7).
+
Irradiation of the crystalline dienone (7). which is readily accessible from cyclopentanone and benzaldehyde, and
which is used as a cosmetic light protection agent (UV-A
range)‘,], results in formation of the spiroheterocyclic compound (9) via cleavage of the five-membered ring and subsequent cycloaddition to the C=O-bond of a second molecule of (7). Furthermore (7) dimerizes via the exocyclic
double bonds to give the dispirocyclobutanes (10) and (11).
The product ratios (9) :(lo):(11)=26 :38 : 8 do not change,
whether or not (7) is crystallized slowly from methanol, or
rapidly from dichloromethane, and whether or not air is excluded during irradiation. However, neither (9) nor (10).
but almost exclusively the head to head dimer (11) is
formed in solution (dichloromethane; h> 380 nm)Isl upon
irradiation of (7).
Ph
Procedure
\
SnCI, (25 mol%) is added slowly to a constantly stirred
solution of the terf-alkyl chloride (I0 mmol) and trimethylsilyl cyanide (2) (13 mmol) in 30 mL of anhydrous CH2CI,
at room temperature under N2. After 24-38 h the solution
is poured onto ice-water and shaken vigorously. The organic phase is separated off, the aqueous phase washed
twice with CH2CI2, and the combined organic phases
washed with a 1OYo solution of NaHC03. The solution is
dried over Na2S04,concentrated, and either distilled or recrystallized.
+Yh
Ph P h
Received: January 12, 1981,
publication delayed at the authors’ request [Z 912 IE]
German version: Angew. Chem. 93. 1075 (1981)
[ I ] R. Gompper, Angew. Chem. 76, 412 (1964);Angew. Chem. Int. Ed. Engl.
3. 560 (1964).
121 N . Kornblum, R. A . Smiley. R. K. Bluckwood. D. C. Iffland. 1. Am. Chem.
SOC.77. 6269 (1955).
[31 B. Sauille. Angew. Chem. 79, 966 ( 1967);Angew. Chem. Int. Ed. Engl. 6.
928 (1967); T.4.Hor Hard and Soft Acids and Bases Principle in Organic Chemistry, Academic Press, New York 1977.
141 K . Friedrich. K . Wullenfe/s in Z . Rappoporr. S. Porai: The Chemistry of
the Cyano Group, Wiley-lnterscience, New York 1970,p. 67.
151 L. Friedmon. H . Shechfer. J. Org. Chem. 25. 877 (1970).
161 L. I . Krimen. D. J . Cora. Org. React. 17, 213 (1969).
171 S. Hiinig, G. Wehner. Synthesis 1979. 522;J. K. Rasmussen, S. M. Heilmun, ibid. 1979. 523.
181 B. U. Trosf,Acc. Chem. Res. 7, 85 (1074);M. T. Reerz. W. F. Uuier. I .
Chutziiosifids. A. Gionnis, H . Heimbach, U.Lowe. Chem. Ber. 113. 3741
(1980). Review of methods for the preparation of compounds with quaternary C atoms: S. F. Munin. Tetrahedron 36. 419 (1980).
191 Note added in proof I n the meantime, a procedure has been reported according to which certain tertiary alcohols can be converted into nitriles,
R. Dauis. K. G. Unrch, J. Org. Chem. 46, 2985 (1981).
1018
0 Verlug Chemie GmbH, 6940 Weinheim. 1981
p %,
Ph
( 71
+
Ph.
y
‘0
(10)
(9)
ph
--
Ph
‘b
Ph
The structures and compositions of the dimers (9), (10)
(with mirror symmetry), and (11) (with rotational symmetry) were established by elemental analyses as well as by
IR-, UV-, and ‘H-NMR spectra (see Table 1). (10) and ( Z l )
are characteristically different from their centrosymmetric
stereoisomer[61.
It is unusual that several products are stereoselectively
formed with comparable yields upon irradiation of crystalline (7) (cf. e.g.I6]; further products which appeared in
yields of <4% were not investigated). The formation of (9),
[‘I Prof. Dr. G. Kaupp,
[‘*I
I. Zimmermann
Chemisches Laboratorium der Universitat
Albertstrasse 21, D-7800Freiburg (Germany)
This work was supported by the Deutsche Forschungsgemeinschaft, the
Fonds der Chemischen Industrie and the Wissenschaftliche Gesellschaft
Freiburg i. Br. We thank Dr.D. Hunkler for recording the NMR spectra.
0570-0833/81/1212-1018 $02.50/0
Angew. Chem. h t . Ed Engl. 20 (1981) No I 2
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