Reactions of Diarylnitrenium Ions
-P h en yl-1-[(t r im et h ylsilyl)oxy]et h ylen e (7). The
J . Org. Chem., Vol. 62, No. 9, 1997 2751
1
127.5, 126.5, 122.9, 122.6, 109.3, 44.3, 24.7; HRMS calculated
amount of 1a and 7 used in this case was 0.205 g (0.546 mmol)
and 1.15 mL (1.07 g, 5.60 mmol), respectively. The para
addition product 23 (4.2 mg) was obtained cleanly following
column chromatography (10:1 hexane/EtOAc). The other two
for C16H15NO 237.1154, found 237.1147.
Rea ction w ith 1b. The amount of 1b and 4 used in this
case was 0.168 g (0.416 mmol) and 0.810 g (4.64 mmol),
respectively. Bis(4-methylphenyl)amine 1757 (6.5 mg), N-
addition product 18 (30.9 mg), N-(4-methylphenyl) quinone
imine/para addition product 20 (18.9 mg), and N-(p-tolyl)-3,3,5-
trimethylindolinone 19 (28.7 mg) were obtained cleanly fol-
lowing two rounds of column chromatography (5:1 hexane/
products, Ph
gether. After a second round of chromatography using 4:1
hexane/CH Cl , Ph NH (8.3 mg) and 26 (4.2 mg) were obtained
cleanly. The overall yield for this reaction was 35.5%: 23:
2
NH and N-phenylindole 26, were isolated to-
2
2
2
1
recrystallized from EtOH, mp 122-123 °C; H NMR (CDCl
3
)
2 2
EtOAc followed by 4:1 hexane/CH Cl ). In the first round, 17
δ 8.03-7.99 (m, 2H), 7.54-7.40 (m, 3H), 7.27-6.89 (m, 9H),
and 18 were isolated as a mixture, separate from 19 and 20;
19 and 20 were isolated together. Both mixtures were
separated in the second round. The overall yield for this
5
1
1
.71 (br s, 1H, N-H), 4.20 (s, 2H); 13C (CDCl
41.9, 136.6, 133.0, 130.3, 129.2, 128.5, 126.7, 120.8, 117.9,
17.7, 44.7; HRMS (FAB) calculated for C20 18NO 288.1388,
3
) δ 197.9, 143.1,
H
reaction was 74.4%. 17: 1H NMR (CDCl
3
) δ 7.06 (d, 8.2 Hz,
found 288.1389.
-Met h oxy-1-[(t r im et h ylsilyl)oxy]p r op en e (3). The
amount of 1a and 3 used in this case was 0.206 g (0.549 mmol)
and 0.905 g (5.64 mmol), respectively. Ph NH (19.2 mg),
N-addition product 15 (11.8 mg), and para addition product
1 (39.0 mg) were obtained cleanly following two rounds of
column chromatography (5:1 hexane/EtOAc, followed by 4:1
hexane/CH Cl ). In the first round, Ph NH and 15 were
isolated as a mixture, separate from 11 and N-phenylindoli-
4H), 6.94 (d, 8.2 Hz, 2H), 5.50 (br s, 1H, N-H), 2.29 (s, 6H).
1
1
4
1
8: H NMR (CDCl
H), 3.74 (s, 3H), 2.29 (s, 6H), 1.46 (s, 6H); C (CDCl
43.8, 131.4, 129.5, 123.7, 61.4, 52.5, 26.3, 20.6; HRMS
3
) δ 7.03 (d, 8.2 Hz, 4H), 6.71 (d, 8.2 Hz,
1
13
3
) δ 178.0,
2
1
calculated for C19
NMR (CDCl ) δ 7.29 (m, 4H), 7.08 (s, 1H), 6.97 (d, 8.0 Hz, 2H),
.71 (d, 8.0 Hz, 2H), 2.40 (s, 3H), 2.35 (s, 3H), 1.46 (s, 6H);
CDCl ) δ 180.7, 140.3, 137.5 135.7, 132.3, 132.2, 130.1, 130.0,
27.7, 126.2, 123.3, 109.1, 44.3, 24.7, 21.1, 21.0; HRMS
2
H23NO 297.1729, found 297.1726. 19: H
1
3
1
3
6
C
(
3
2
2
2
1
1
1
calculated for C H19NO 265.1467, found 265.1456. 20:
H
none 13; 11 and 13 were isolated together (confirmed by H
NMR, HPLC, and GCMS results). The mixture of Ph NH and
5 was separated in the second round. The mixture of 11 and
3 was injected into the HPLC (20 mL, 70:30 CH CN/water).
18
NMR (CDCl
3
) δ 7.11 (d, 8.0 Hz, 2H), 6.73 (d, 8.0 Hz, 2H), 6.48
2
(
m, 2H), 6.36 (m, 2H), 3.69 (s, 3H), 2.33 (s, 3H), 1.21 (m, 6H);
1
1
1
3
C (CDCl
3
) δ 175.9, 156.8, 147.8, 145.5, 143.4, 133.1, 129.9,
3
1
29.3, 120.6, 120.3, 51.7, 48.9, 44.8, 22.2, 21.8, 21.7, 20.8;
Using a concentration curve constructed using a sample of
N-phenylindolinone 13 synthesized by an alternate route,56
mass of 5.9 mg was extrapolated. The mixture of 11 and 13
was then chromatographed (4:1 hexane/CH Cl ). Only the
para addition product 11 was isolated. The overall yield for
HRMS calculated for C H NO 297.1729, found 297.1724.
19 23
2
a
EP R Sp ectr u m fr om P h otolysis of 1a in CH
20 mg, 0.053 mmol) was dissolved in CH CN (10 mL). The
solution was purged for 10 min. with N . A 0.4 mL aliquot of
this solution was transferred to an EPR tube that had been
purged with N . The sample was placed in the EPR cavity,
3
CN. 1a
(
3
2
2
2
1
this reaction was 61.8%. 11: H NMR (CDCl
(
3
) δ 7.28-7.20
m, 4H), 7.06-6.94 (m, 4H), 6.20-6,88 (m, 1H), 5.74 (br s, 1H,
2
1
3
and a background spectrum was taken. As expected, no EPR
spectrum was obtained. The sample was then irradiated for
N-H), 3.67 (q, 1H), 3.65 (s, 3H), 1.47 (d, 3H); C (CDCl
3
) δ
75.5, 143.1, 142.2, 132.9, 129.3, 128.3, 120.9, 117.9, 117.8,
1.9, 44.7, 18.5; HRMS calculated for C16 255.1259,
) δ 7.24-7.17 (m, 4H),
1
5
2
min with a medium-pressure Hg lamp. The spectrum was
H
17NO
2
1
scanned at X-band. The modulation amplitude and frequency
were 2.683 G and 100 kHz, respectively. A signal was
observed at 3480 G. The signal was split into a five-line
pattern with 7 G coupling and no further hyperfine coupling.
A spectrum was simulated using an aN value of 6.0 obtained
from the literature28 and a line broadening of 2.9 G. The
spectrum thus generated was identical to the experimental
spectrum.
found 255.1250. 15: H NMR (CDCl
.97-6.84 (m, 6H), 4.63 (q, 1H), 3.67 (s, 3H), 1.32 (d, 3H);
CDCl ) δ 174.5, 146.1, 129.2, 122.4, 122.2, 57.2, 52.1, 16.8;
HRMS calculated for C16 255.1259, found 255.1261. 13
) δ 7.55-7.04 (m, 8H), 6.80 (m,
3
1
3
6
C
(
3
H
17NO
2
1
(
synthetic): H NMR (CDCl
3
1
3
1
1
1
3
H), 3.61 (q, 1H), 1.58 (d, 3H); C (CDCl ) δ 177.8, 143.8, 134.5,
30.3, 129.4, 127.8, 127.6, 126.4, 123.6, 122.7, 109.1, 53.3, 40.6,
5.5.
La ser F la sh P h otolysis (LF P ) Exp er im en ts w ith 4, 6,
a n d 8. In all cases 60 mg (0.159 mmol) of 1a was dissolved
1
-Meth oxy-1-[(tr im eth ylsilyl)oxy]-2-m eth ylpr open e (4).
Rea ction w ith 1a . The amount of 1a and 4 used in this case
was 0.202 g (0.537 mmol) and 0.935 g (5.37 mmol), respec-
in 60 mL of CH
stirrer. The solution was purged with dry N
3
CN in a flow cell equipped with a magnetic
for 10 min. The
2
tively. Ph
addition product 12 (40.4 mg), and N-phenylindolinone 14
24.3 mg) were obtained cleanly following two rounds of column
chromatography (5:1 hexane/EtOAc followed by 4:1 hexane/
CH Cl ). In the first round, Ph NH and N-addition product
6 were isolated as a mixture, separate from the para addition
2
NH (7.3 mg), N-addition product 16 (11.8 mg), para
nucleophile was added neat, via microliter syringe in all cases.
The nucleophile concentration range over which kinetic data
(
-3
were collected for alkenes 4, 6, and 8 was 0-5.6 × 10 , 0-4.3
-
3
-3
×
10 , and 0-3.2 × 10 M, respectively. The wavelength at
2
2
2
which data was collected was 425 nm. The decay waveforms
obtained in these experiments were fitted using a pseudo-first-
order decay function. The values for the pseudo-first-order
rate constants thus obtained were then plotted versus increas-
ing concentration for each nucleophile. The second-order rate
constant was obtained from the linear least-squares fit of these
data.
1
product 12 and N-phenylindolinone 14; 12 and 14 were
isolated together. Both mixtures were separated in the second
round. The overall yield for this reaction was 65.9%. 12: 1
H
NMR (CDCl
6
3
) δ 7.28-7.20 (m, 4H), 7.06-6.98 (m, 4H), 6.94-
.87 (m, 1H), 5.71 (br s, 1H, N-H), 3.64 (s, 3H), 1.56 (s, 6H);
3
1
C (CDCl
3
) δ 177.4, 143.1, 141.7, 137.0, 129.2, 126.5, 120.9,
1
2
(
1
6
17.8, 117.5, 52.1, 45.8, 26.5; HRMS calculated for C17H19NO
2
Ack n ow led gm en t. The authors thank the NSF for
their generous support of this work.
1
69.1416, found 269.1412. 16: H NMR (CDCl ) δ 7.29-7.21
3
m, 4H), 7.03-6.96 (m, 2H), 6.83-6.79 (m, 4H) 3.75 (s, 3H),
1
3
.48 (s, 6H); C (CDCl
3
) δ 177.8, 146.0, 128.9, 123.8, 122.1,
269.1416,
, 400 MHz) δ 7.55-7.51
m, 2H), 7.44-7.40 (m, 3H), 7.29-7.28 (m, 1H), 7.20-7.17 (m,
Su p p or t in g In for m a t ion Ava ila b le: 1H and 13C NMR
spectra of the compounds characterized in this study (33
pages). Color maps of the molecular electrostatic potentials
obtained from the DFT densities and pictures of Kohn-Sham
1.5 52.6, 26.4; HRMS calculated for C17
H
19NO
2
1
found 269.1409. 14: H NMR (CDCl
(
1
(
3
H), 7.12-7.10 (m, 1H), 6.87-6.85 (m, 1H), 1.50 (s, 6H); 13
, 400 MHz) δ 180.7, 142.9, 135.6, 134.6, 129.5, 127.8,
C
+
+
+
2
LUMO’s for PhNH , Ph N , and Ph(Ac)N are available
CDCl
3
electronically. This material is contained in libraries on
microfiche, immediately follows this article in the microfilm
version of the jounal, and can be ordered from the ACS; see
any current masthead page for ordering information.
(
56) Rodriguez, A. C.; Leeming, P. R. J . Med. Chem. 1972, 15, 762-
70.
57) Barton, D. H. R.; Donnelly, D. M. X.; Finet, J .-P.; Guiry, P. J .
J . Chem. Soc., Perkin Trans. 1 1991, 9, 2095-2102.
7
(
J O9623649