H-Atom Abstraction and Silyl-Transfer Photoreactions
J . Org. Chem., Vol. 61, No. 10, 1996 3313
CH2Cl2) of the residue obtained by concentration of the
photolysate gave 85 mg (28%) of 27 (mp 54-55 °C), 46 mg
(21%) of 28 (mp 123-125 °C); 34 mg (11%) of 29 (mp 84-85
°C), and 20 mg (6%) of 30 (mp 70-71 °C).
41: 1H NMR 2.60 (br s, 1 H, OH), 4.23 and 4.35 (AB q, J )
9.5 Hz, 4 H, H-2, and H-4), 5.11 (s, 2 H, PhCH2), 7.28-7.49
(m, 10 H, aromatic); 13C NMR 64.4 (C-2 and C-4), 66.9 (PhCH2),
71.9 (C-3), 124.5, 128.0, 128.1, 128.1, 128.5, and 128.8 (aro-
matic, CH), 136.5 and 142.8 (aromatic, ipso), 156.6 (NCdO);
IR 3500-3400, 1685, 1451, 1357, 757, 698; LRMS (CI) m/z 284
(M + 1, 10), 224 (5), 220 (7), 178 (15), 148 (23), 134 (31), 120
(90), 105 (100); HRMS m/z 283.1212 (C17H17NO3 requires
283.1208).
27: 1H NMR 0.07 (s, 9 H, SiMe3), 0.72 (dd, J ) 14.9, 9.2
Hz, 1 H, CH2Si), 1.03 (dd, J ) 14.9, 5.8 Hz, 1 H, CH2Si), 2.96
(m, 1 H, CH-), 3.33 (m, 1 H, NCH2), 3.44 (m, 1 H, NCH2),
6.84 (s, 1 H, NH), 7.5-7.9 (m, 4 H, arom); 13C NMR -0.8
(SiMe3), 18.0 (CH2Si), 44.3 (CH2N), 52.1 (CH), 128.4, 129.7,
131.2, 132.0, 132.1, 136.8 (arom), 171.1, 207.0 (CdO); IR 1678;
LRMS m/z 262 (M + 1, 5), 229 (5), 217 (20), 195 (21), 160 (27);
HRMS (CI) m/z 262.1263 (C14N20NO2Si requires 262.1264).
28: 1H NMR 1.45 (m, 1 H), 2.24 (m, 2 H), 2.58 (m, 1 H),
3.23 (m, 1 H, CHN), 3.49 (m, 1 H, CHN), 3.88 (s, 1 H, OH),
7.32-7.53 (m, 4 H, arom); 13C NMR 27.6 (CH2), 34.6 (CH2),
41.2 (NCH2), 96.4 (quart. C), 122.5, 123.4, 129.5, 131.6, 132.6,
147.3 (arom), 170.1 (CdO); IR 3300 (br), 1684; LRMS m/z 189
(M, 100), 174 (14), 172 (67), 170 (38), 161 (80); HRMS m/z
189.0790 (C11H11NO2 requires 189.0790).
42: 1H NMR 0.17 (br s, 9 H, SiCH3), 4.17 (d, J ) 9.8 Hz, 1
H, H-4), 4.23 (s, 1 H, H-2), 4.56 (d, J ) 9.8 Hz, 1 H, H-4), 5.09
(s, 2 H, PhCH2), 7.25-7.45 (m, 10 H, aromatic); 13C NMR -1.7
(SiCH3), 64.9 (C-4), 66.8 (PhCH2), 69.3 (C-2), 75.1 (C-3), 124.5,
127.8, 128.0, 128.2, 128.4, and 128.8 (aromatic, CH), 136.7 and
144.7 (aromatic, ipso), 156.5 (NCdO); IR 3500-3400, 3030,
2951, 1684, 845, 698; LRMS m/z 355 (M, 0.65), 340 (12), 264
(10), 236 (30), 220 (100), 206 (25), 192 (99.98), 177 (34), 130
(21), 120 (30), 105 (35); HRMS m/z 355.1599 (C20H25NO3Si
requires 355.1604).
43: 1H NMR 0.04 (s, 9 H, SiCH3), 2.66 (d, J ) 5.5 Hz, 2 H,
SiCH2), 4.51 (br s, 1 H, NH), 5.08 (s, 2 H, PhCH2), 7.34 (m, 5
H, aromatic); 13C NMR -2.87 (SiCH3), 26.9 (SiCH2), 66.8
(PhCH2), 128.1, 128.2, and 128.5 (aromatic, CH), 136.7 (aro-
matic, ipso), 157.3 (NCdO); IR 3400-3300, 3034, 2955, 1700,
1540, 1273, 858; LRMS m/z 237 (M, 0.18), 236 (0.92), 220 (23),
178 (7), 146 (13), 102 (48), 91 (100), 73 (96), 59 (5); HRMS m/z
237.1162 (C12H19NO2Si requires 237.1185).
29: 1H NMR -0.01 (s, 9 H, SiMe3), 1.62 (s, 1 H, OH), 3.74
(dd, J ) 15.7, 5.8 Hz, 1 H, NCH2), 4.12 (dd, J ) 15.7, 3.4 Hz,
1 H, NCH2), 5.68 (s, 1 H, NCH), 5.74 (d, J ) 9.2 Hz, 1 H,
dCHSi), 5.90 (ddd, J ) 9.2, 5.8, 3.4 Hz, 1 H, HCd), 7.40-7.82
(m, 4 H, arom); 13C NMR -1.4 (SiMe3), 43.5 (NCH2), 81.3
(NCH), 123.3 (HCd), 123.4 (HCd), 129.9, 131.5, 132.3, 133.2,
139.9, 143.9 (arom), 167.1 (CdO); IR 3300 (br), 1683; LRMS
m/z 261 (m, 14), 246 (10), 232 (100), 204 (26), 177 (10), 133
(12), 130 (11); HRMS m/z 261.1185 (C14H19NO2Si requires
261.1186).
P h otoch em istr y of r-Silyla m id oa ceton a p h th on e 13. A
solution of the amidonaphthone 13 (53 mg, 0.13 mmol) in CH3-
CN (100 mL) was irradiated with Pyrex glass-filtered light
under N2. The reaction progress was followed by UV, TLC,
and 1H NMR which showed that >90% of 13 consumed after
3 h. The photolysate was concentrated in vacuo to give a
residue which was subjected to column chromatography
(Alumina, 20% ether/cyclohexane) to yield 6 mg (11%) of
recovered amidonaphthone 13, ca. 2 mg (5%, 1H NMR integra-
tion) of benzyl carbamate 43, 3 mg (6%) of 1-[(benzyloxy)-
carbonyl]-3-(2-naphthyl)-3-[(trimethylsilyl)oxy]azetidine (44),
6 mg (15%) of 1-[(benzyloxy)carbonyl]-3-hydroxy-3-(2-naph-
thyl)azetidine (45), 0.5 mg (1%) of 1-[(benzyloxy)carbonyl]-2-
(trimethylsilyl)-3-hydroxy-3-(2-naphthyl)azetidine (46), and 3
mg (14%) of 2-acetonaphthone.
30: 1H NMR 0.02 (s, 9 H, SiMe3), 2.87 (s, 3 H, CH3O), 3.75
(dd, J ) 15.7, 6.0 Hz, 1 H, NCH2), 4.52 (dd, J ) 15.7, 3.8 Hz,
1 H, NCH2), 5.81 (d, J ) 18.7 Hz, 1 H, dCHSi), 5.82 (s, 1 H,
NCHO), 5.96 (ddd, J ) 18.7, 6.0, 3.8 Hz, 1 H, CHd), 7.47-
7.86 (m, 4 H, aromatic); 13C NMR -1.3 (SiMe3), 43.9 (NCH2),
49.3 (CH3O), 85.9 (NCH), 123.5 (dCHSi), 123.6 (CHd), 129.9,
132.0, 133.1, 133.4, 139.7, 140.5 (arom), 167.4 (CdO); IR 1697;
LRMS m/z 275 (M, 15), 261 (21), 260 (100), 244 (19), 224 (12),
205 (12), 202 (35); HRMS m/z 275.1347 (C15H21NO2Si requires
275.1342).
In Aceton e. Irradiation of a solution of (silylpropyl)-
phthalimide 11 (500 mg, 1.91 mmol) in 200 mL of acetone with
Vycor-filtered light under N2 for 20 h (58% conversion of 11)
gave after concentration in vacuo and chromatography of the
residue (silica, 1:4 EtOAc-CH2CH2) 63 mg (22%) of 27, 16 mg
(8%) of 28, 82 mg (28%) of 29, and 27 mg (9%) of 30.
In 30% H2O-MeCN. A solution of 11 (220 mg, 0.84 mmol)
in a solution of 65 mL of MeCN and 35 mL of H2O was
irradiated with Vycor-filtered light under N2 for 20 min. The
photolysate was conentrated in vacuo to give 153 mg (96%) of
28, a crystalline solid (mp 121-124 °C). One recrystallization
from acetone-hexane gave 144 mg (91%) of pure 28 (mp 123-
125 °C).
44: 1H NMR 0.03 (s, 9 H, SiCH3), 4.35 (m, 4 H, H-2 and
H-4), 5.13 (s, 2 H, PhCH2), 7.29-7.91 (m, 12 H, aromatic); 13
C
NMR 1.44 (SiCH3), 64.4 (C-2 and C-4), 66.9 (PhCH2), 73.3 (C-
3), 123.5, 123.5, 126.3, 126.4, 127.6, 128.0, 128.1, 128.2, 128.5,
and 128.7 (aromatic, CH), 132.8, 132.9, 136.6, and 141.0
(aromatic, ipso), 156.6 (NCdO); IR 3059, 2955, 1709, 1420,
1356, 1252, 1105, 843, 750; LRMS m/z 405 (M, 1.24), 390 (22),
314 (10), 299 (13), 243 (12), 242 (43), 241 (20), 227 (28), 171
(13), 170 (100), 155 (32), 141 (16), 128 (22), 127 (18); HRMS
m/z 405.1727 (C24H27NO3Si requires 405.1760).
45: 1H NMR 3.23 (s, 1 H, OH), 4.29 and 4.41 (AB q, J ) 9.3
Hz, 4 H, H-2 and H-4), 5.11 (s, 2 H, PhCH2), 7.31-7.90 (m, 12
H, aromatic); 13C NMR 64.3 (C-2 and 4), 67.0 (PhCH2), 71.9
(C-1), 122.7, 123.3, 126.4, 126.5, 127.6, 128.0, 128.1, 128.2,
128.5, and 128.8 (aromatic, CH), 132.8, 133.0, 136.5, and 140.1
(aromatic, ipso), 156.7 (NCdO); IR 3392, 3055, 2952, 1684,
1429, 1356, 1185, 1105, 748; LRMS m/z 333 (M, 0.5), 242 (15),
198 (8), 178 (11), 171 (38), 170 (100), 156 (12), 155 (84), 142
(15), 141 (54), 134 (18), 128 (74), 127 (44); HRMS m/z 333.1360
(C21H19NO3 requires 333.1365).
P h otoch em istr y of r-Silyla m id oa cetop h en on e 12.
A
solution (75 mL) of CH3CN containing 327 mg (0.92 mmol) of
the amido phenone 12 was irradiated with Corex glass-filtered
light under N2 for 1 h (>90% conversion). The photolysate
was concentrated in vacuo giving a residue which was sub-
jected to column chromatography (Alumina, 20% ether-
cyclohexane) to yield 31 mg (9%) of recovered amidophenone
12, 73 mg (22%) of 1-[(benzyloxy)carbonyl]-3-phenyl-3-[(tri-
methylsilyl)oxy]azetidine (40), 35 mg (13%) of 1-[(benzyloxy)-
carbonyl]-3-hydroxy-3-phenylazetidine (41), 29 mg (9%) of
1-[(benzyloxy)carbonyl]-2-(trimethylsilyl)-3-hydroxy-3-phen-
ylazetidine (42), and trace quantities of acetophenone and
benzyl N-[(trimethylsilyl)methyl]carbamate (43). The product
40 was converted to 41 with the treatment by 1.0 N aqueous
H2SO4 in THF at 25 °C.
46: 1H NMR 0.2 (br s, 9 H, SiCH3), 4.24 (d, J ) 8.8 Hz, 1
H, H-4), 4.34 (br s, 1 H, H-2), 4.68 (br s, 1 H, H-4), 5.11 (s, 2
H, PhCH2), 7.29-7.86 (m, 12 H, aromatic); IR 3500-3400,
1694, 1682, 1417, 845, 748; LRMS m/z 405 (M, 4.96), 404 (5),
391 (12), 390 (38), 314 (28), 299 (17), 282 (23), 270 (34), 252
(10), 242 (24), 241 (100), 236 (25), 227 (30), 206 (19), 192 (52),
170 (98), 155 (70), 141 (19), 128 (32), 127 (41), 107 (22); HRMS
m/z 405.1775 (C24H27NO3Si requires 405.1760).
P h otoch em istr y of γ-(Tr im eth ylsilyl)bu tyr op h en on e
(14). A 0.5 mL CD3CN solution containing 5 mg (0.024 mmol)
of the phenyl ketone 14 was irradiated with Corex glass-
filtered light for 35 min. The reaction progress was monitored
by 1H NMR. The yield of the photoproducts, acetophenone,
1,4-diphenyl-1,4-butanedione, and vinyltrimethylsilane, were
40: 1H NMR 0.00 (s, 9 H, SiCH3), 4.28 (s, 4 H, H-2, and
H-4), 5.10 (s, 2 H, PhCH2), 7.21-7.43 (m, 10 H, aromatic); 13
C
NMR 1.3 (SiCH3), 64.5 (C-2 and C-4), 66.7 (PhCH2), 73.0 (C-
3), 124.9, 127.7, 127.9, 128.0, 128.4, and 128.6 (aromatic, CH),
136.5 and 143.7 (aromatic, ipso), 156.4 (NCdO); IR 3018, 2959,
1693, 1216, 1116, 769; LRMS (CI) m/z 356 (M + 1, 3), 266 (5),
264 (3), 193 (22), 192 (100), 191 (62), 190 (6), 179 (7), 178 (9),
177 (57), 130 (8); HRMS (CI) m/z 356.1693 (M + 1, C20H26
NO3Si requires 356.1682).
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