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Formation of Oxiranes from Methyl(phenyl)selenoniomethanide and Aldehydes or Ketones.

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Table 1. Selected physical data of compounds (21, (5). (9) and (10).
Cpd.
Yield
IW
[Route]
4
OCOPh
M.p.
I"C1
IR (Paraffin) [cm-'1
80-83
189-191
189-191
198-201
1710 bs, 1544 s
3180 bs, 1684 s
3270 bm, 1630 s
3280 w, 3200 m, 3060 w, 1702 s, 1644 s
42 -43
182- 183
177-179
131-132
1670 s. 1532 s
3200 bm, 1626 m
3210 bm, 1578 m
3280 m, 1698 s, 1630 bs
Iel
131 - 134
141- 143
66-68
169-170
123-124
1702 bs, 1534 bs
3120 bs, 1626 s
3280 s, 3200 m, 3080 m, 1700 s, 1650 s
1680 bs, 1538 bs
3240 bm, 1628 w
3430 m, 1700 s, 1666 s
[a] From ( I ) [b] From (2). [c] From (5). Id] From (9). [el B.p.=92-96"C/O.O5
torr. [fJ 'H-NMR (242 K): 6 = 1.33 (s, 3 H), 1.66 (s, 3 H), 1.33-3.03 (br. m,
9H), 3.76 (d, J = 3 Hz, 1 H), 5.67 (br. s, 1 H).
lc
3
s
(10)
(l)-llO)
n
R R
a
b
I
2
2
2
AH-CH==CH-CH=
4H-CH4H-CH=
H H
H
H
H H
4 H P h
C
d
R"
R"'
Route
1, I I
I, I1
I1
I
Scheme I . a : HZCO,MezNH .HCI, EtOH, reflux, 0.5-4 h. b: NaOH or KF,
iPrN02, reflux, 4 h. c: Zn, NH,CI, aqueous THF, 0", 3 h. d : freshly reduced
Fe, HCI, aqueous EtOH, reflux, 3 h. e : PhCOCI, ether, room temp., 1 h.f: 2 N
NaOH, aqueous EtOH, reflux, 2 h. g : 2% CHaCOIH in CH3C02H, room
temp., 4 h. h: Ac?O, CCI,, HCIO,, room temp., 16-48 h. i: m-CIChH4CO2H,
CH2CIZ,room temp., 24 h. j : 2 N HCI, EtOH. reflux. 2H. k : hv, EtOh, 420 h. I : FeSO,, aqueous EtOH, 2 h.
(10) (Scheme 1). Two distinct routes from the y-nitroketones (2) to the oxaziridines (6) have been developed. In
route 1 the nitroketones (2) are converted by reductive cyclization into the bicyclic nitrones (3). which on treatment
with benzoyl chloride undergo 0-benzoylation and allylic
rearrangementf2' to the benzoyloxy- I-pyrrolines (41, and
can readily be saponified to the alcohols (5). Treatment of
(5) with peracetic acid affords isomerically pure oxaziridines (6) having cis-coupled rings (assignment of the structures was confirmed by 'H-NMR spectroscopy). In route
11, the y-nitroketones (2) are converted via the enol acetates (7) and their epoxides into the a-hydroxy-y-nitroketones (8),which undergo reductive cyclization to the bicyclic nitrones (9). Photorearrangement of (9) affords cis- and
trans-(6j.
Both routes are suitable for the synthesis of lactams
( I O U ) and (lob) (see Table 1). ( I & ) is only accessible via
Angeu. Chem. In!. Ed. Engl. 20 (1981) No. 8
route 11 since (3c) rapidly decomposes. It is significant that
the stability of the hydroxynitrones (9) is, in general, much
greater than that of the nitrones (3); route 11 is generally
preferable to route I, where both are applicable. Route I,
however, was chosen for the synthesis of the benzylidenesubstituted lactam (IOd) because of the expected lack of selectivity in the peracid oxidation of the benzylidene-enol
acetate (7d). The C=N-double bond in (Sd) can be oxidized, without concomitant epoxidation of the C=C-double
bond, to form (6d) in high yield.
Isolation of (6) is not required in either route I or 11. Indeed, nitrones (9) can be irradiated in ethanol and the concentrated reaction solution treated directly with iron(ir)
sulfate to afford the lactams (10). The 'H-NMR spectra of
the latter compounds at room temperature generally consist of broad signals, which indicates that the systems are
considerably flexible. The low temperature spectra are,
however, much sharper.
The overall reaction (1)+(10) permits a three-atom condensative ring-expansion of cyclic ketones.
Received: January 8, 1981 [ Z 802b IE]
German version: Angew. Chem. 93,704 (1981)
[I] D. St. C. Black, L. M . Johnstone, Angew. Chem. 93, 703 (1981); Angew.
Chem. Int. Ed. Engl. 20, 669 (1981).
121 N . J . A. Gutleridge. 1. R. M . Dales. J. Chem. SOC.C 1971, 122.
131 N . S . Gill. K. B. James, F. Lions. K . T. Poffs,J. Am. Chem. SOC. 7 4 , 4923
(1952).
Formation of Oxiranes from
Methyl(pheny1)selenoniomethanide and Aldehydes
or Ketones
By Ken Takaki. Masateru Yasumura, and
Kenji NegoroI']
Organoselenium compounds have been widely investigated in the last decade"]. Selenium ylides, in which carbanions are stabilized by a carbonyl group, react with a,&
unsaturated ketones to give cyclopropanes'*]. However,
their reactivities, especially those of non-stabilized ylides,
[*I Prof. Dr. K. Negoro, Dr. K. Takaki, DipLChem. M. Yasumura
Department of Applied Chemistry, Faculty of Engineering
Hiroshima University, Sendamachi-3, Hiroshima 730 (Japan)
0 Verlag Chemie GmbH, 6940 Weinheim, 1981
0570-0833/81/0808-0671 $02.50/0
671
have not been as completely investigated as sulfonium and
phosphonium ylides.
We report here on reactions of methyl(pheny1)selenoniomethanide ( I ) with carbonyl compounds (2), which afford oxiranes (31 in good yields (Table 1).
PhSe
@
p
3
s
'HZ
::c
+
R" 'R2
B
R'
+ PhSeCH,
R2
Table 1. Selected data of the oxiranes (3) obtained from methyl(pheny1)selenoniomethanide ( I ) and carbonyl compounds (2). (3a), (36). (3e) and (3fl
show molecular ions in the mass spectrum.
Cpd.
la1
R'
130)
(3b)
(3c)
(34
13e)
(38
Ph
H
p-NO,C,H,
H
n-C6H I3
H
n-C4H.,
CH,
n-C,Hq
CZH,
4CHd-
R'
Yield
19/01[b]
B. p.
["C/torr]
94
82
83-85/15
Icl
-
76
88
83
55- 57/75
62-65/25
46-48/23
Cpd.
'H-NMR (6,T M S int., in C D C I )
(30)
2.70 (dd, J = 5.5 and 2.7 Hz, 1 H), 3.05 (dd, J = 5.5 and 4.0 Hz, 1 H),
3.73 (dd, J=4.0 and 2.7 Hz, 1 H), 7.03-7.40 (m. S H )
(3b)
2.73(dd,J=5.8and2.8Hz,lH),3.20(dd,J=5.8and4.0Hz,IH),
(3d)
(3e)
(38
[I] H. J. Reich, Acc. Chem. Res. 12, 22 (1979).
[2l N. N. Magdesieua. L. N. Ngu. N . M. Koloskoua. J. Org. Chem. USSR 13,
928 (1977).
[31 B. M. Trost. L. S. Melvin. Jr.: Sulfur Ylides, Academic Press, New York
1975.
[4] D. L. Klayman, W. H.H. Ciinrher: Organic Selenium Compounds: Their
Chemistry and Biology, Wiley-Interscience, New York 1973.
151 H. M. Gilow. G. L. Walker, J. Org. Chem. 32,2580 (1967).
3.93(dd,J=4.0and2.8Hz, lH),7.40(d,J=8.4Hz,2H),S.l5(d,
J = 8.4 Hz, 2 H)
0.73-1.63 (t and m , J = 7 . 0 Hz, IZH), 2.30-2.60 (m. ZH)
0.77-1.87 (t and m, J=7.0 Hz, 14H),2.20-2.67 (m,ZH)
0.83-2.06 (m. lOH), 2.33-2.60 (m, 2 H )
[a] The products (3) were identified by comparison with authentic samples
prepared from dimethylsulfoniomethanide and the corresponding carbonyl
compounds 131. [b] Yields were determined by NMR. [c] M.p.=83-85"C.
The ylide ( I ) was generated in situ from dimethylphenylselenonium methyl sulfate and sodium hydride in the presence of carbonyl compounds (2), since selenium ylides
are relatively unstable and undergo fission of the ylide
bondsi4I. Generally, these reactions are mild and result in
good yields of ketones and aromatic aldehydes. In the
reaction with heptanal (2c) GC analysis of the reaction
mixture showed a small peak, in addition to those of the
educts, which may be assigned to the expected oxirane (3c),
the isolation of which was, however, difficult. These epoxidations are the first examples, to o u r knowledge, of reactions of non-stabilized selenium ylides with "enolizable"
carbonyl compounds.
Experimental Evidence for the IH,SSH,I* Radical
Cation in Solution
By Shamim A . Chaudhri and Klaus-Dieter Asmus"'
The H,S molecule and radical species derived from it
have been the subjects of numerous investigations. The
ionization and excitation energies, as well as geometrical
parameters, for example, have been calculated using various theoretical models"] and the results compared with
experimental values[*]. Recently,
has used theoretical calculations (HF/4-31G, MP2/4-31G and MNDO) to
consider some thermodynamic and optical characteristics
of an [H2SSHz]tradical cation.
A significant feature of [H2SSH2]i is assumed to be a
three-electron bond; two p-electrons forming a o-bond
and the third, unpaired electron being promoted into an
antibonding o*-orbital. A corresponding three electron
bond has been experimentally well established irr the analogous [R,SSR,]t radical cations formed as intermediates
in the oxidation of t h i o e t h e r ~ ' ~ .We
~ ' . are now able to present experimental evidence on the formation, stability and
optical absorption spectrum of [H,SSH,jt for purpose of
comparison with Clark's calculations.
The experiments were carried out using a pulse radiolysis technique. 'OH and H' react with H2S according to
HZS
+ 'OH/H
+
H S + HZO/HI
to yield H S radicals (k.o,=lO'o and kH.=109 mol-' L
s - ' ) ~ ~The
] . H S radicals exhibit no detectable optical absorption in the UV/VIS-region as is apparent from, for example, pulse radiolysis investigations (aqueous solutions,
p H = 3 , lo-, mol/L H,S). At higher H,S concentrations,
( e . 9 . lo-' mol/L and lower p H values ( e . g . with 0.2 mol/L
HCIO,), however, a well characterized transient optical absorption band can be observed in the UV (A,,,=370 nm;
Fig. la).
General Procedure
A solution of dimethyl(pheny1)selenonium methyl sulfate['] (12 mmol) and the aldehyde or ketone (10 mmol) in
dry dimethylformamide (30 mL) is added dropwise over a
period of 30 min to a stirred suspension of NaH (12 mmol)
in dry tetrahydrofuran (30 mL); all operations were conducted under nitrogen and the mixture was cooled on an
ice bath. The mixture was then warmed to room temperature for 4 h and held at 50°C for 30 min. After cooling,
10% aqueous NH,Cl (20 mL) was added and the organic
layer extracted with ether, washed with NaCl solution, and
dried over Na2S04. Evaporation of the solvent in uacuu
gave a residue which contained the oxirane (3). methyl
phenyl selenide (4), and a small amount of unreacted (2).
Distillation of the residue afforded analytically pure (3).
Received: September 8, 1980 [Z 804 IE]
German version: Angew. Chem. 93, 707 (1981)
672
0 Verlag Chernre GmbH, 6940 Weinheim, 1981
Afnm
Fig. I . a ) UVNIS-absorption spectrum of the [H>SSH:]C radical cation, measured immediately after a 4 ps pulse in an aqueous solution of lo-' mol/L
H2S and 0.2 mol/L HCIO,, b) UV/VIS-absorption spectrum after decay of
[H2SSHz]r(ca. 0.5 ms after pulse).-Optical density (OD) in arbitary units.
[*) Prof. Dr. K.-D. Asmus, Dr. S. A. Chaudhri
Hahn-Meitner-lnstitut fur Kernforschung Berlin GmbH,
Bereich Strahlenchemie
Postfach 3901 28, D-1000 Berlin 39 (Germany)
0570-0833/81/0808-0672
$02.50/0
Angew. Chem. Inr. Ed. Engl 20 (1981) No. 8
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