(
1-Hydroxycyclopropyl)- and (1-Hydroxycyclobutyl)carbene
893
the organic and aqueous layers were separated, and the latter
was extracted with diethyl ether (2Â 20 mL). The organic layers
were combined, washed with saturated sodium bicarbonate
Conflicts of Interest
The authors declare no conflicts of interest.
(
2Â 20 mL), and freed of solvent at the rotary evaporator. The
Acknowledgements
final product, a white solid, was recrystallized from hexanes and
ethyl acetate. Yield: 63 %. dH (500 MHz, CDCl ) 8.01–7.95
(
D.M.T. acknowledges funding from the United States National Science
Foundation (grant number CHE-1665278) for support of this work.
3
m, 2H), 7.40 (dd, J 5.0, 2.2, 2H), 7.31–7.22 (m, 4H), 2.50
d, J 4.4, 2H), 1.99 (s, 1H), 0.92–0.86 (m, 2H), 0.77–0.72 (m, 1H),
(
0
1
.67–0.60 (m, 2H). d (126MHz, CDCl ) 134.9, 129.4, 128.8,
C
27.7, 126.1, 123.1, 56.0, 30.9, 24.5, 12.7.
References
3
[
Synthesis of exo-1-(1a,9b-Dihydro-1H-cyclopropa[l]
phenanthren-1-yl)cyclobutan-1-ol (35)
(
e) H. M. Frey, Adv. Photochem. 1966, 4, 225.
The monobromo derivative 34 (2.71 g, 10 mmol) was dissolved
in 100 mL dry THF and cooled to À708C. Then, t-butyllithium
2
(1.7 M in pentane, 13 mL, 22 mmol) was added dropwise over
(
1
0 min, keeping the temperature below À658C. The resulting
dark green reaction mixture was left stirring at À708C for 1 h.
Cyclobutanone (0.9 mL, 13.7 mmol) was added to the reaction
mixture, which was left stirring for an additional 45 min at
À708C. The solution slowly warmed to room temperature, and
2
2] (a) R. Bonneau, M. T. H. Liu, in Advances in Carbene Chemistry
(
was quenched with the addition of saturated aqueous NH Cl
4
1
(25 mL). The resulting mixture was poured into a separatory
funnel and the reaction flask was rinsed with Et O (10 mL) and
(
2
3
H O (10 mL). The rinses were added to the separatory funnel
2
[
and the aqueous layer was separated from the organic suspen-
sion of the product. The aqueous layer was then extracted
(
(
Ed. U. H. Brinker) 1998, Vol. 2, pp. 1–28 (JAI Press: Stamford, CT).
b) M. S. Platz, in Advances in Carbene Chemistry (Ed. U. H. Brinker)
with Et O (2 Â 25 mL) and the extracts were combined with the
1998, Vol. 2, pp. 133–174 (JAI Press: Stamford, CT).
2
organic suspension. The suspension was washed sequentially
with H O (2 Â 25 mL) and brine (1 Â 25 mL). The solvent was
2
[
[
[
removed to obtain a crude yellow product, which was recrys-
tallized from hexanes and ethyl acetate. Yield: 68 %. dH
(500 MHz, C D ) 7.87–7.79 (m, 2H), 7.27–7.20 (m, 2H), 7.15–
6 6
7.04 (m, 4H), 2.49 (d, J 4.5, 2H), 1.88–1.74 (m, 4H), 1.46 (dtd,
J 11.5, 9.4, 4.6, 1H), 1.19 (dp, J 11.3, 8.8, 1H), 1.02 (s, 1H), 0.46
(m, 1H). d (126 MHz, C D ) 128.8, 127.9, 127.8, 127.6, 127.4,
C 6 6
1
25.9, 123.2, 73.0, 35.9, 22.8, 12.0.
(
Photolysis Experiments
[
Photolysis was performed at room temperature in a Rayonet
photochemical reactor equipped with 16 30-cm 8-W lamps with
output centred at ,350 nm (range ,315 to 400 nm). In a typical
photolysis experiment, the carbene precursor (,10–15 mg) was
weighed out and dissolved in 0.6 to 0.8 mL of benzene-d6. The
resulting solution was then placed in an NMR tube (glass) for the
2
[
9] J. M. Nguyen, D. M. Thamattoor, Synthesis 2007, 2093.
[
1
[
11] CIF files for the two precursors have been deposited at the Cambridge
Crystallographic Data Centre (CCDC). CCDC deposition numbers are
1945138 for 32 and 1945137 for 35.
1
13
photolysis and initial H and C spectra were taken. The pho-
1
tolysis was monitored by H NMR, until it was deemed that all
precursor was consumed.
[12] For a recent theoretical discussion of the structure and chemistry of
[
Supplementary Material
Spectral data for precursors 32 and 35 and photolysis results are
available on the Journal’s website.