colorless oil after purification (EtOAc–PE = 1 : 2). Rf = 0.26.
1H NMR: 4.59–4.51 (m, 5H), 4.33 (d, J = 5.6 Hz, 1H), 4.08
(t, J = 6.4 Hz, 1H), 4.01 (dd, J = 9.6, 6.9 Hz, 1H), 3.30 (s,
6H), 3.14–3.09 (m, 1H), 2.86 (dd, J = 13.0, 9.6 Hz, 1H), 2.59
(dd, J = 12.2, 6.6 Hz, 1H), 2.42–2.38 (m, 2H), 2.04–1.87 (m,
3H), 1.98 (dd, J = 13.0, 6.9 Hz, 1H), 1.81–0.99 (m). IR: 1717.
HRMS (FAB) calculated for C19H29O5 (MHϩ) 337.2015, found
337.2021.
to room temperature and stirred for 16 h. The reaction was
quenched by the addition of saturated aqueous NaHCO3
(1 mL). The aqueous phase was extracted with EtOAc (3 ×
2 mL). The combined organic layers were washed with brine
(2 mL), dried over MgSO4 and concentrated in vacuo. Purifi-
cation by chromatography (EtOAc–PE = 2 : 1) afforded 29 (24
mg, 72%) as a colorless oil. Rf = 0.28. 1H NMR (CD3OD): 4.22
(dd, J = 11.8, 2.2 Hz, 1H), 3.96 (d, J = 10.4 Hz, 1H), 3.83
(dd, J = 8.0, 2.9 Hz, 1H), 3.65 (d, J = 10.4 Hz, 1H), 3.48
(s, 1H), 3.28 (d, J = 11.8 Hz, 1H), 2.77–2.70 (m, 1H), 2.01–1.90
(m, 2H), 1.94 (dd, J = 12.1, 2.8 Hz, 1H), 1.79 (dd, J = 12.1,
8.0 Hz, 1H), 1.66–1.51 (m, 4H), 1.45–1.34 (m, 1H), 1.19–1.01
(m, 21H).
Cycloadduct 25. According to general procedure A, irradi-
ation of alkene 14 (120 mg, 0.38 mmol) for 1 h afforded 25 (114
mg, 95%), as a crystalline solid after purification by recrystal-
lisation from acetone–n-hexane. Colourless crystals, mp 186–
187 ЊC. 1H NMR: 4.67 (d, J = 3.9 Hz, 1H), 4.02 (s, 1H), 2.34 (dt,
J = 13.3, 4.5 Hz, 1H), 2.23 (br d, J = 13.0 Hz, 1H), 2.17–2.07
(m, 2H), 1.97–1.90 (m, 3H), 1.81–1.42 (m, 12H), 1.07–0.95
(m, 1H). 13C NMR: 174.5, 165.2, 110.5, 78.4, 78.0, 60.5, 57.8,
46.8, 36.9, 34.8, 34.6, 24.5, 22.2, 22.1, 21.7, 21.6, 21.3, 20.6. IR:
1783, 1740. HRMS (FAB) calculated for C18H23O5 (MHϩ)
319.1545, found 319.1553.
Crystal data 25.‡ C18H22O5, Mr = 318.36, monoclinic, P21/c,
a = 6.6011(5), b = 16.1185(1), c = 14.513(1) Å, β = 91.431(7)Њ,
V = 1543.7(2) Å3, Z = 4, Dx = 1.37 g cmϪ3, λ(Cu-Kα) = 1.5418
Å, µ(Cu-Kα) = 8.2 cmϪ1, F(000) = 680, 243 K, crystal size
0.25 × 0.30 × 0.35 mm3. 3172 reflections measured, 2586 unique
(Rint = 0.050) which were used in all calculations. The final
wR(F 2) was 0.053 (all data).
Tetrahydrofuran 30
To a solution of 29 (24 mg, 0.062 mmol) in pyridine (1 mL)
was added, tosyl chloride (24 mg, 0.12 mmol). The resulting
mixture was stirred for 1 h and then quenched by the addition
of saturated aqueous NaHCO3 (1 mL). The aqueous phase was
extracted with EtOAc (3 × 2 mL). The combined organic layers
were washed with brine (2 mL), dried over MgSO4 and con-
centrated in vacuo. Purification by chromatography (EtOAc–
PE = 1 : 3) afforded 30 (23 mg, 97%) as a colorless oil. Rf = 0.26.
1H NMR: 3.99 (d, J = 4.5 Hz, 1H), 3.95 (d, J = 2.2 Hz, 2H),
3.69 (d, J = 8.9 Hz, 1H), 3.55 (d, J = 8.9 Hz, 1H), 2.85 (d, J = 2.3
Hz, 1H), 2.55 (dt, J = 14.1, 4.7 Hz, 1H), 1.92–1.81 (m, 2H),
1.67–1.42 (m, 6H), 1.33–1.19 (m, 1H), 1.17–0.98 (m, 21H). 13
C
NMR: 82.9, 80.9, 69.0, 61.7, 54.7, 53.1, 52.8, 33.9, 23.6, 22.1,
21.6, 20.7, 18.0, 11.9. HRMS (FAB) calculated for C21H39O3Si
(MHϩ) 367.2668, found 367.2672.
Cycloadduct 26. According to general procedure A, irradi-
ation of alkene 17 (32 mg, 0.088 mmol) for 30 min afforded 26
(28 mg, 88%), as a colorless oil after purification by chromato-
1
graphy (EtOAc–PE = 1 : 5). Rf = 0.24. H NMR: 4.86 (s, 1H),
7a-(tert-Butyldiphenylsilyloxymethyl)-1-hydroxymethyl-octa-
hydro-1,3a-methanoindene-3,8-diol (32)
4.19 (d, J = 13.0 Hz, 1H), 4.10 (dd, J = 8.7, 1.6 Hz, 1H), 3.44
(d, J = 13.0 Hz, 1H), 2.91 (dd, J = 12.7, 8.7 Hz, 1H), 2.20–2.16
(m, 1H), 1.98 (dd, J = 12.7, 1.6 Hz, 1H), 1.80–1.35 (m, 16H),
1.39 (s, 3H), 1.37 (s, 3H), 1.21–1.15 (m, 1H). 13C NMR: 171.1,
106.0, 102.3, 78.5, 73.1, 69.9, 54.0, 47.4, 39.6, 36.4, 35.7, 33.4,
30.4, 27.3, 24.8, 24.7, 23.8, 22.8, 22.6, 22.1, 19.5. IR: 1721.
HRMS (FAB) calculated for C21H31O5 (MHϩ) 363.2171, found
363.2176.
To a solution of 27 (20 mg, 0.088 mmol) in DMF (1 mL) were
added at 0 ЊC, imidazole (30 mg, 0.44 mmol) and TBDPSCl
(34 µL, 0.13 mmol). The resulting mixture was allowed to
warm to room temperature and stirred for 16 h. The reaction
was quenched by the addition of saturated aqueous NaHCO3
(1 mL). The aqueous phase was extracted with EtOAc (3 ×
2 mL). The combined organic layers were washed with brine
(2 mL), dried over MgSO4 and concentrated in vacuo. Purifi-
cation by chromatography (EtOAc–PE = 5 : 1) afforded 32 (18
mg, 44%) as a white solid. Rf = 0.25. 1H NMR (CD3OD): 7.68–
7.65 (m, 4H), 7.47–7.37 (m, 6H), 4.42 (dd, J = 11.0, 1.8 Hz, 1H),
3.93 (d, J = 11.5 Hz, 1H), 3.76 (dd, J = 7.8, 2.8 Hz, 1H), 3.61
(d, J = 11.5 Hz, 1H), 3.48 (s, 1H), 3.38 (d, J = 11.0 Hz, 1H),
2.80–2.74 (m, 1H), 2.09–2.05 (m, 1H), 1.97–1.38 (m, 3H), 1.50–
1.30 (m, 4H), 1.06 (s, 9H), 0.96–0.90 (m, 1H). 13C NMR
(CD3OD): 137.2, 136.9, 134.7, 134.4, 131.1, 131.0, 129.0, 83.5,
72.8, 63.8, 59.9, 57.6, 50.6, 37.9, 27.7, 24.7, 23.7, 22.8, 22.5,
20.3.
1,7a-Bis(hydroxymethyl)octahydro-1,3a-methanoindene-3,8-diol
(27)
To a solution of LiAlH4 (1 M in THF, 2.0 mL, 2.0 mmol) was
added in small portions, cycloadduct 25 (120 mg, 0.38 mmol).
The reaction mixture was stirred for 5 min. Then, the reaction
was quenched by addition of EtOAc and saturated aqueous
Na2SO4 (10 drops) was added. The resulting mixture was stirred
for 1 h. After addition of additional solid Na2SO4 the mixture
was filtered through Celite® and concentrated in vacuo. Purifi-
cation by chromatography (EtOAc : acetone = 1 : 1) afforded
27 (52 mg, 60%) as a white powder. Mp 173 ЊC. 1H NMR
(CD3OD): 4.21 (dd, J = 11.4, 2.2 Hz, 1H), 3.83 (dd, J = 7.9, 2.9
Hz, 1H), 3.76 (d, J = 11.2 Hz, 1H), 3.47 (s, 1H), 3.41 (d, J = 11.2
Hz, 1H), 3.32 (d, J = 11.4 Hz, 1H), 2.77–2.70 (m, 1H), 1.98–
1.88 (m, 3H), 1.78 (dd, J = 12.1, 8.0 Hz, 1H), 1.65–1.51 (m, 4H),
1.41–1.34 (m, 1H). 13C NMR (CD3OD): 83.6, 72.8, 61.5, 58.9,
57.5, 57.2, 50.2, 38.0, 25.1, 23.8, 22.7. HRMS (FAB) calculated
for C12H21O4 (MHϩ) 229.1440, found 229.1437.
TBDPS acetonide (33)
To a solution of 32 (18 mg, 0.039 mmol) in DMF (1 mL)
were added, 2,2-dimethoxypropane (24 µL, 0.20 mmol) and a
catalytic amount of PPTS. The resulting mixture was stirred for
4 h. The reaction was quenched by the addition of saturated
aqueous NaHCO3 (1 mL). The aqueous phase was extracted
with EtOAc (3 × 2 mL). The combined organic layers were
washed with brine (2 mL), dried over MgSO4 and concentrated
in vacuo. Purification by chromatography (EtOAc–PE = 2 : 3)
afforded 33 (16 mg, 80%) as a colorless oil. Rf = 0.33. 1H NMR:
7.68–7.64 (m, 4H), 7.44–7.35 (m, 6H), 4.24 (dd, J = 10.8, 1.7
Hz, 1H), 4.22 (d, J = 11.9 Hz, 1H), 3.96 (d, J = 11.9 Hz, 1H),
3.95–3.90 (m, 1H), 3.53 (d, J = 10.8 Hz, 1H), 3.43 (s, 1H), 3.25–
3.18 (m, 1H), 2.17 (br d, J = 13.9 Hz, 1H), 1.90 (d, J = 4.4 Hz,
1H), 1.75–1.50 (m, 5H), 1.44 (s, 3H), 1.43–1.36 (m, 1H), 1.36
(s, 3H), 1.25–1.07 (m, 1H), 1.07 (s, 9H). 13C NMR: 135.9, 135.8,
7a-Hydroxymethyl-1-triisopropylsilyloxymethyloctahydro-1,3a-
methanoindene-3,8-diol (29)
To a solution of 27 (20 mg, 0.088 mmol) in DMF (1 mL)
were added at 0 ЊC, imidazole (30 mg, 0.44 mmol) and TIPSCl
(28 µL, 0.13 mmol). The resulting mixture was allowed to warm
p1/b1/b104165g/ for crystallographic files in .cif or other electronic
format.
J. Chem. Soc., Perkin Trans. 1, 2001, 2250–2256
2255