9366 J. Am. Chem. Soc., Vol. 122, No. 39, 2000
Lee and FalVey
through a 320 nm cutoff filter in 1a and a 395 nm cutoff filter in 2a.
Solutions of 10-15 mg of the reactants were dissolved in 1.5 mL of
CD3CN which contained 0.5 equiv of hexamethyldisiloxane as an
internal standard. The sample solutions were purged with N2. The yield
of released CH3CO2H was determined at various photolysis times by
1H NMR peak integration (δ 1.98 ppm) relative to the starting material
(using the peak at 5.34 ppm) and the internal standard. Formation of
1b from photolysis of 1a was also quantified by 1H NMR through
integration of its peak at δ 2.59. The identity of this product was further
verified by GC/MS analysis of the photoproduct mixtures [Shimadzu
QP-5000 system with XTI-5, 30 M 5% phenyl column and electron-
impact mass spectrometry (EIMS) detection]. 1b was the only product
detected with this method. 1b was also isolated using preparative thin-
layer chromatograpy (TLC) in 60% yield from a preparative photolysis
of 1a.
4-Carbo-(9-anthrylmethoxy)phenacyl Acetate (2a). Compound 2a
was prepared from 4-(R-Acetoxyacetyl)benzoic acid, (4, 0.70 g) and
9-hydroxymethylanthracene (6) using the procedure for 1a. This
provides 0.36 g (30%) of 2a as a dark yellow solid; mp 184-186 oC;
1H NMR (CDCl3) δ 2.18 (s, 3H), 5.25 (s, 2H), 6.41 (s, 2H), 7.54 (m,
4H), 7. 84 (d, J ) 8 Hz, 2H), 8.05 (t, J ) 9 Hz, 4H), 8.41 (d, J ) 9
Hz, 2H), 8.53 (s, 1H); 13C NMR (CDCl3) δ 191.8, 170.8, 165.7, 137.9,
134.5, 131.4, 131.2, 130.2, 129.5, 129.2, 127.6, 126.8, 125.7, 125.2,
123.8, 66.1, 59.9, 20.5; HRMS (FAB) calcd for C26H21O5 [M + H]+
413.1389; found, 413.1414.
4-Carbo-(9-anthrylmethoxy)acetophenone (2b). Compound 2b
was prepared from 6 and 4-acetylbenzoic acid (7, 0.637 g, 3.89 mmol)
using the procedure for 1a. This provides 0.520 g (49%) of 2b as a
1
yellow solid: mp 118-120 °C; H NMR (CDCl3) δ 2.57 (s, 3H),
6.41 (s, 2H), 7.52 (t, J ) 8 Hz, 2H), 7.59 (d, J ) 8 Hz, 2H), 7.90 (d,
J ) 9 Hz, 2H), 8.05 (m, 4 H), 8.41 (d, J ) 9 Hz, 2H), 8.53 (s, 1H); 13
C NMR (CD3CN) δ 197.5, 165.5, 140.3, 133.7, 131.4, 130. 9, 129.5,
129.3, 129.0, 128.2, 126.8, 126.3, 125.3, 124.0, 59.6, 26.2; HRMS calcd
for C24H18O3 354.1256; found, 354.1228.
4-Carbo-(3-N,N-dimethylaminobenzyloxy)phenacyl acetate (1a).
Compound 1a was prepared from 4-(R-acetoxyacetyl)benzoic acid 4
and 3-(N,N-dimethylamino)benzyl alcohol 5. DCC (0.72 g, 3.15 mmol)
and 4 (0.70 g, 3.15 mmol, see Supporting Information) were dissolved
in 7 mL of dry THF. After 15 min of stirring, 5 (0.52 g, 3.47 mmol,
see Supporting Information) and a catalytic amount of N,N-(dimethyl-
amino)pyridine (DMAP) (38.5 mg, 0.32 mmol) were added to the
reaction flask. A yellow byproduct, dicyclohexylurea, began to
precipitate out after 1 h. The solution was allowed to stand at room
temperature for 48 h. The reaction was not complete at this point by
TLC, but a workup was performed. The precipitate was removed by
filtration, and filtrates were washed with saturated NH4Cl, and then
water. The aqueous layer was extracted with ether. Organic layers were
combined, washed with water, and dried over MgSO4. The resulting
solution was concentrated under vacuum. Purification with flash column
chromatography using 65:35 hexane/ethyl acetate solvent system gave
1a as a yellow solid (0.14 g, 21%); mp 86-88 °C; UV λmax (MeCN),
4-Carbomethoxyphenacyl acetate (8). First 4-carbomethoxy-
acetophenone (9) was prepared by combining CH2N2 and 4-acetylben-
zoic acid 7 (1.64 g) using Smissman’s procedure.29 This provides 9
(1.69 g, 95%) as silky needles: mp 94-95 °C (lit27 mp 95.0-95.5
°C). Compound 9 was then brominated using a published procedure30
to give R-bromo-4-(carbomethoxy)acetophenone as fine light orange
1
powder in 91% yield: mp 134-136 °C; H NMR (CDCl3) δ 3.95 (s,
3H), 4.46 (s, 2H), 8.03 (d, J ) 9 Hz, 2H), 8.14 (d, J ) 9 Hz, 2H); 13
C
NMR (CD3CN) δ 191.3, 165.8, 137.5, 134.5, 129.6, 128.8, 52.1, 32.9;
HRMS calcd for C10H9O379Br 255.9735; found, 255.9727. This latter
compound (0.64 g) was combined with NaOAc in absolute MeOH to
give 8 (see the preparation of 4 in the Supporting Information).
Compund 8 was obtained as white crystals (0.92 g, 64%): mp 150-
152 °C dec; UV (λmax MeCN), 248 nm (logꢀ ) 4.20), 290 nm (log ꢀ
1
252 nm (log ꢀ ) 4.45), 300 nm (log ꢀ ) 3.48); H NMR (CD3CN) δ
2.13 (s, 3H), 2.91 (s, 6H), 5.29 (s, 2H), 5.34 (s, 2H), 6.73 (m, 2H),
6.82 (d, J ) 2 Hz, 1H), 7.21 (t, J ) 8 Hz, 1H), 7.99 (d, J ) 8 Hz, 2H),
8.12 (d, J ) 8 Hz, 2H); 13C NMR (CDCl3) δ 191.9, 170.3, 165.4, 150.7,
137.3, 136.3, 134.8, 130.1, 129.4, 127.7, 116.4, 112.5, 112.3, 67.9,
66.1, 40.5, 20.5; HRMS (FAB) calcd for C20H22O5N [M + H]+
356.1498; found, 356.1518.
1
) 3.11); H NMR (CDCl3) δ 2.21 (s, 3H), 3.94 (s, 3H), 5.32 (s, 2H),
7.94 (d, J ) 9 Hz, 2H). 8.13 (d, J ) 9 Hz, 2H); 13C NMR (CD3CN)
δ 193.5, 171.0, 166.7, 138.4, 135.5, 130.6, 128.8, 67.3, 53.0, 20.6;
HRMS calcd for C12H12O5 236.0685; found, 236.0690.
Acknowledgment. This work was partially supported by the
Chemistry Division of the National Science Foundation and a
Semester Research Award from Graduate Research at the
University of Maryland.
4-(Carbo-3-N,N-dimethylaminobenzyloxy)acetophenone (1b). A
solution of 3-(N,N-dimethylamino)benzyl alcohol, 5 in pyridine (2.63
mL) at 0 °C was treated with 4-acetyl benzoyl chloride (0.6789 g, 3.72
mmol, see Supporting Information). The solution was heated at 60 °C
for 1 h 20 min. The dark brown crude mixture was then poured into
20 mL H2O, and the aqueous solution was extracted with three 15-mL
portions of ether. The organic layers were combined and washed with
10% aqueous HCl solution, saturated. NaHCO3, and then H2O. The
resulting solution was concentrated under vacuum. The resulting crude
brown oil was purified using flash column chromatography with 3:2
hexane/ethyl acetate as the elutant. A yellow oil was obtained which
solidified upon standing. 0.606 g, 62%; mp 61-62 °C; 1H NMR
(CDCl3) δ 2.62 (s, 3H), 2.95 (s, 6H), 5.32 (s, 2H), 6.77 (m, 3H), 7.23
Supporting Information Available: 1H NMR spectra for
1a, 1b, 2a, 2b, and 8. Transient spectrum from direct excitation
of 9. Preparation procedures and characterization data for
synthetic intermediates 3, 4, 5, and 4-acetylbenzoyl chloride
(PDF). This material is available free of charge via the Internet
JA9939441
(t, J ) 8 Hz, 1H), 8.13 (d, J ) 7 Hz, 2H), 8.15 (d, J ) 7 Hz, 2H) 13
C
NMR (CDCl3) δ 197.6, 165.6 150.7, 140.2, 136.4, 134.1, 129.9, 129.4,
128.2, 116.4, 112.5, 112.3, 67.8, 40.5, 26.9; HRMS calcd for C18H19O3N
297.1365; found, 297.1360.
(29) Smissman, E. E.; Li, J. P.; Israili, Z. H. J. Org. Chem. 1968, 33,
4231-4235.
(30) Rather, J. B.; Reid, E. E. J. Am. Chem. Soc. 1919, 41, 77-83.