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K. Cocq et al.
Cluster
Synlett
(12) The term ‘carbo-fulvene’ is employed here for the first time. The
actual nomenclature of B is: 1,4,7,10-tetraphenyl-13-(propan-
2-ylidene)cyclopentadeca-1,2,3,7,8,9-hexaen-5,11,14-triyne.
(13) In tentative efforts aiming at accessing the carbo-quinoid A,
conditions for a selective reaction of the ene-di(ynone) 9 with
TMS-C≡C–Li could not be found. In an alternative approach,
attempts at mesylation–elimination at the isopropylcarbinol
vertices of the [6]periclynediol 2 also failed to produce A.
(14) (a) Leroyer, L.; Lepetit, C.; Rives, A.; Maraval, V.; Saffon-Merce-
ron, N.; Kandaskalov, D.; Kieffer, D.; Chauvin, R. Chem. Eur. J.
2012, 18, 3226. (b) Baglai, I.; de Anda-Villa, M.; Barba-Barba, R.
M.; Poidevin, C.; Ramos-Ortíz, G.; Maraval, V.; Lepetit, C.;
Saffon-Merceron, N.; Maldonado, J.-L.; Chauvin, R. Chem. Eur. J.
2015, 21, 14186.
(19) Chauvin, R. J. Phys. Chem. 1992, 96, 9194.
(20) Liebeskind, L. S.; South, M. S. J. Org. Chem. 1980, 45, 5426.
(21) Eakins, G. L.; Alford, J. S.; Tiegs, B. J.; Breyfogle, B. E.; Stearman,
C. J. J. Phys. Org. Chem. 2011, 24, 1119.
(22) Maraval, V.; Leroyer, L.; Harano, A.; Barthes, C.; Saquet, A.;
Duhayon, C.; Shinmyozu, T.; Chauvin, R. Chem. Eur. J. 2011, 17,
5086.
su:gran:firefly:index.html) which is partially based on the
GAMESS (US) source code. (b) Schmidt, M. W.; Baldridge, K. K.;
Boatz, J. A.; Elbert, S. T.; Gordon, M. S.; Jensen, J. H.; Koseki, S.;
Matsunaga, N.; Nguyen, K. A.; Su, S.; Windus, T. L.; Dupuis, M.;
Montgomery, J. A. J. Comput. Chem. 1993, 14, 1347.
(24) DFT calculations at the B3PW91/6-31G(d,p) level on the crude
crystallographic nuclear geometry of 12 (without re-optimiza-
tion of the C–H bond lengths), give an indicative HOMO–LUMO
gap of 0.090 Ha, corresponding to a one-electron excitation
wavelength of 506 nm (see Supporting Information). The transi-
tion associated to the observed lower λmax value (421 nm) thus
likely involves excitations of higher energy, such as HOMO – 1 →
LUMO or HOMO → LUMO + 1 as in the Gouterman model shown
to apply to carbo-benzene systems (see ref. 14). The HOMO and
LUMO here also involve the main π system and are spread out
over both the cyclopentadienone and [14]annulene rings of 12
(see Figures in Supporting Information).
(15) The parent tetraphenyl-carbo-benzene, was, however, obtained
in the presence of an undetermined impurity evidenced by 1H
NMR spectroscopy, see ref. 10b.
(16) CCDC 1479480 (1) and 1479481 (12) contain the supplemen-
tary crystallographic data for this paper. The data can be
obtained free of charge from The Cambridge Crystallographic
(17) (a) Maurette, L.; Tedeschi, C.; Sermot, E.; Soleilhavoup, M.;
Hussain, F.; Donnadieu, B.; Chauvin, R. Tetrahedron 2004, 60,
1077. (b) Leroyer, L.; Zou, C.; Maraval, V.; Chauvin, R. C. R. Chim.
2009, 12, 412.
(18) The conversion of 10 to 12 proceeded in three steps.
(i) First Step
(25) The calculation of the formal ‘total oxidation level’ ζ of an
organic molecule proceeds in two steps. First, the carbon skele-
ton is fully saturated (to sp3C centers only) by hydration (addi-
tion of H2O) of all the insaturations, and fully oxygenated by
replacement of all the C–heteroatom bonds by a C–O bond if the
heteroatom is more electronegative than C or by a C–H bond in
the contrary case. Then ζ is equated to the total number of (sin-
gle) C–O bonds.
A solution of impure 10 (74 mg) in CH2Cl2 (15 mL) was treated at
0 °C with Et3N (0.32 mL, 2.30 mmol) and mesyl chloride (0.18
mL, 2.33 mmol). The resulting mixture was stirred for 2 h at 0
°C, before dilution with CH2Cl2 (20 mL). After successive treat-
ments with distilled water, sat. aq solution of NaHCO3, 1 N aq
solution of HCl, and extractions with CH2Cl2, the combined
organic layers were washed with brine, dried over MgSO4, and
concentrated under reduced pressure without going to dryness.
(ii) Second Step
The concentrated solution resulting from the first step was
diluted with CHCl3 (20 mL) and treated at r.t. with silica (2 g).
The mixture was stirred for 4 h at r.t., before filtration through
Celite® and concentration under reduced pressure without
going to dryness.
(26) Chen, B.; Xie, X.; Lu, J.; Wang, Q.; Zhang, J.; Tang, S.; She, X.; Pan,
X. Synlett 2006, 259.
(27) Frisch, M. J.; Trucks, G. W.; Schlegel, H. B.; Scuseria, G. E.; Robb,
M. A.; Cheeseman, J. R.; Scalmani, G.; Barone, V.; Mennucci, B.;
Petersson, G. A.; Nakatsuji, H.; Caricato, M.; Li, X.; Hratchian, H.
P.; Izmaylov, A. F.; Bloino, J.; Zheng, G.; Sonnenberg, J. L.; Hada,
M.; Ehara, M.; Toyota, K.; Fukuda, R.; Hasegawa, J.; Ishida, M.;
Nakajima, T.; Honda, Y.; Kitao, O.; Nakai, H.; Vreven, T.;
Montgomery, J. A. Jr.; Peralta, J. E.; Ogliaro, F.; Bearpark, M.;
Heyd, J. J.; Brothers, E.; Kudin, K. N.; Staroverov, V. N.;
Kobayashi, R.; Normand, J.; Raghavachari, K.; Rendell, A.;
Burant, J. C.; Iyengar, S. S.; Tomasi, J.; Cossi, M.; Rega, N.; Millam,
N. J.; Klene, M.; Knox, J. E.; Cross, J. B.; Bakken, V.; Adamo, C.;
Jaramillo, J.; Gomperts, R.; Stratmann, R. E.; Yazyev, O.; Austin,
A. J.; Cammi, R.; Pomelli, C.; Ochterski, J. W.; Martin, R. L.;
Morokuma, K.; Zakrzewski, V. G.; Voth, G. A.; Salvador, P.;
Dannenberg, J. J.; Dapprich, S.; Daniels, A. D.; Farkas, Ö.;
Foresman, J. B.; Ortiz, J. V.; Cioslowski, J.; Fox, D. J. Gaussian 09,
Revision A.01; Gaussian, Inc: Wallingford CT, 2009.
(iii) Third Step
The concentrated solution obtained from the second step was
diluted with CH2Cl2 (20 mL) and treated at –78 °C with SnCl2
(310 mg, 1.63 mmol). The resulting mixture was stirred for 20
min at –78 °C and for 2.5 h at r.t., before filtration through
Celite® and silica gel and concentration under reduced pres-
sure. Purification by silica gel chromatography (pentane–
CH2Cl2, 8:2) afforded 12 as orange crystals (4 mg, 7.3 mmol, 6%
yield from 4 or 11).
Analytical Data for Compound 12
1H NMR (400 MHz, 298 K, CDCl3): δ = 1.85 (d, 3JH–H = 6.7 Hz, 6 H,
CH(CH3)2), 5.80 (m, 1 H, –CH(CH3)2), 7.40–7.81 (m, 12 H, m-, p-
(28) Schleyer, P. v. R.; Maerker, C.; Dransfeld, A.; Jiao, H. J.; Hommes,
J. R. V. J. Am. Chem. Soc. 1996, 118, 6317.
3
C6H5 and -C1,2,3H), 8.30 (d, JH–H = 7.6 Hz, 1 H, -C4H), 8.64, 8.71,
8.78 (3 d, 3 3JH–H = 7.4 Hz, 3 × 2 H, o-C6H5, without assignment).
13C{1H} NMR (100 MHz, 298K, CDCl3): δ = 25.12 (CH(CH3)2),
31.49 (CH(CH3)2), 124.17, 124.28, 129.19, 129.31, 129.43,
129.68, 129.82, 129.88, 130.51, 134.43, 135.60 135.95, 137.40,
137.98, 149.33 (o-, m-, p-C6H5 and -C1,2,3,4H, not assigned),
196.40 (>C=O). MS (DCI/CH4): m/z (%) = 546.3 (100) [M]+. HRMS
(DCI/CH4): m/z [M]+ calcd for C42H26O: 546.1984; found:
546.2006. UV-vis: λmax (toluene) = 421 nm. FT-IR: ν = 730 (s),
(29) Wolinski, K.; Hinton, J. F.; Pulay, P. J. Am. Chem. Soc. 1990, 112,
8251.
(30) Poater, J.; Duran, M.; Solà, M.; Silvi, B. Chem. Rev. 2005, 105,
3911.
(31) Corminboeuf, C.; Heine, T.; Seifert, G.; Schleyer, P. v. R.; Weber, J.
Phys. Chem. Chem. Phys. 2004, 6, 273.
(32) Turias, F.; Poater, J.; Chauvin, R.; Poater, A. Struct. Chem. 2016,
27, 240.
1262 (s), 1723 (s), 2924 (s) cm–1
.
© Georg Thieme Verlag Stuttgart · New York — Synlett 2016, 27, 2105–2112