3.2. Synthesis
trop–Si(H)Me2 (1a): 5-Chloro-5H-dibenzo[a,d]cycloheptene (10.02 g, 44.20 mmol, 1.0 equivalent) and elementary lithium (0.71 g, 102.31 mmol, 2.3 equivalents) were reacted in dry tetrahydrofuran (40 mL) at a.T. overnight. The resulting dark red liquid was added dropwise to a solution of chlorodimethylsilane (5.4 mL, 4.60 g, 48.63 mmol, 1.1 equivalents) in dry tetrahydrofuran (40 mL) over an ice bath. The resulting yellow liquid was allowed to warm to a.T. and stirred overnight. The turbid suspension was concentrated under reduced pressure and subsequently distilled in high vacuum (only one fraction was observed from 90 to 115 °C). The obtained yellow liquid was placed in the fridge to give a white, crystalline solid after three days, which was triturated with dry diethyl ether (10.0 mL) and dried in high vacuum (8.328 g, 33.26 mmol, yield: 75.3%).
1H NMR (300 MHz, CDCl3, jb071.1.4) δ 7.27–7.09 (m, 6H, HAr), 7.06 (dd, 3JHH = 7.4 Hz, 4JHH = 1.4 Hz, 2H, H-4,6), 6.74 (s, 2H, H-10,11), 4.18–4.07 (m, 1H, SiH), 3.49 (d, 3JHH = 4.1 Hz, 1H, H-5), −0.09 (d, 3JHH = 3.6 Hz, 6H, SiCH3) ppm. 13C NMR (75 MHz, CDCl3, jb071.1.4) δ 140.83 (s, 2C, Cquart), 135.05 (s, 2C, Cquart), 132.59 (s, 2C, C-10,11), 129.59 (s, 2C, CAr), 129.13 (s, 2C, C-4,6), 128.96 (s 2C, CAr), 125.71(s, 2C, CAr), 47.60 (s, 1C, C-5), −3.71 (s, 2C, Si(CH3)2) ppm. ATR IR: λ−1: 3015 (w, =C–H st), 2955 (w, –C–H st), 2143 (m, Si–H st), 868 (s), 796 (s), 726 (s), 446 (s) cm−1. Elemental analysis: C (81.29%, calc.: 81.54%); H (7.37%, calc.: 7.24%).
trop–SiMe3 (1b): 5-Chloro-5H-dibenzo[a,d]cycloheptene (4.32 g, 19.06 mmol, 1.0 equivalent) and elementary lithium (0.33 g, 47.55 mmol, 2.5 equivalents) were reacted in dry tetrahydrofuran (30 mL) at a.T. overnight. The resulting deep red liquid was added dropwise to a colorless solution of trimethylsilyl chloride (3.2 mL, 2.74 g, 25.21 mmol, 1.3 equivalents) in dry tetrahydrofuran (35 mL). The reaction mixture was allowed to warm to a.T. and stirred overnight. The solvent of the orange solution was removed under reduced pressure to give an orange solid. The crude product was purified by sublimation (up to 150°C, HV) to give a yellow, crystalline solid (4.20 g, 15.88 mmol, yield: 83.3%).
1H NMR (300 MHz, C6D6, jb121.1.3) δ 7.08 (ddd, 3JHH = 7.5 Hz, 3JHH = 6.1 Hz, 4JHH = 2.7 Hz, 2H, H-3,7), 7.06–6.92 (m, 4H, H-1,2,8,9), 6.86 (d, 3JHH = 7.4 Hz, 2H, H-4,6), 6.48 (s, 2H, H-10,11), 3.41 (s, 1H, H-5), −0.06 (s, 9H, SiCH3) ppm. 13C NMR (75 MHz, C6D6, jb121.1.3) δ 140.91 (s, 2C, C-4a,5a), 135.49 (s, 2C, C-9a,11a), 132.86 (s, 2C, C-10,11), 129.95 (s, 2C, C-1,9), 129.73 (s, 2C, C-4,6), 129.07 (s, 2C, C-3,7), 125.71 (s, 2C, C-2,8), 50.24 (s, 1C, C-5), −0.39 (s, 3C, SiCH3) ppm. Elemental analysis: C (81.70%, calc.: 81.76%); H (7.74%, calc.: 7.62%).
Litrop: Method A: Lithium sand (0.348 g, 50.20 mmol, 2.3 equivalents) was suspended in dry tetrahydrofuran (10 mL) and placed in a cooling bath (propan-2-ol and dry ice). 5-Chloro-5H-dibenzo[a,d]cyclo-heptene (5.00 g, 22.06 mmol, 1.0 equivalent) was dissolved in dry tetrahydrofuran (30 mL). The resulting light yellow solution was added dropwise (during 25 min) to the brown suspension. The reaction mixture was allowed to warm to a.T. and a color change to dark red was observed under heat development. After two hours, the dark red liquid was concentrated to approximately 25 mL and filtered over a plug of celite. The resulting red solution was layered with dry n-hexane (71 mL) and stored in the freezer (−23 °C, 6 days). A first crop of green, crystalline needles was obtained (0.479 g, 1.26 mmol, yield: 2.5%; according to 1H NMR spectroscopy, the compound contained 2.5 equivalents of THF). The supernatant was layered with dry n-hexane (30 mL) and stored in the freezer (−23 °C, 1 day) and a second crop was obtained (7.448 g, 19.68 mmol,1 yield: 94.0%, overall yield: 95.0%).
Method B: (5H-Dibenzo[a,d]cycloheptene-5-yl)-dimethyl-silane (1a, 0.159 g, 0.64 mmol, 1.0 equivalent) was dissolved in dry 1,2-dimethoxyethane (2.0 mL). The resulting slightly yellow solution was added to a white suspension of lithium tert-butoxide (0.051 g, 0.64 mmol, 1.0 equivalent) in dry 1,2-dimethoxyethane (2.0 mL) (in a solvent with lower polarity (such as diethyl ether or tetrahydrofuran), a significantly lower yield was obtained). A swift color change to dark red was observed and the reaction mixture was stirred at a.T. (3 h). The dark red liquid was filtered over glass filter paper and celite, layered with dry n-hexane (10.0 mL) and stored in the freezer (−30 °C, overnight). The light yellow supernatant was discarded and the obtained green crystals were washed with dry n-hexane (3 × 1 mL) and dried under a stream of argon (0.1170 g, 0.35 mmol, yield: 55.2%; according to 1H NMR spectroscopy, the compound contained 1.5 equivalents of dme).
1H NMR (300 MHz, C6D6/THF-d8, jb070.1.6) δ 5.70 (td, 3JHH = 7.5 Hz, 4JHH = 1.6 Hz, 2H, H-3,7), 5.15 (td, 3JHH = 7.1 Hz, 4JHH = 1.3 Hz, 2H, H-2,8), 4.87 (dd, 3JHH = 7.1 Hz, 4JHH = 1.6 Hz, 2H, H-1,9), 4.59 (dd, 3JHH = 7.9 Hz, 4JHH = 1.3 Hz, 2H, H-4,6), 3.92 (s, 2H, H-10,11), 1.54 (s, 1H, H-5) ppm. 1H NMR (400 MHz, THF-d8, jb070.1.7) δ 4.80–4.73 (m, 2H, H-3,7), 4.12–4.05 (m, 2H, H-2,8), 3.73–3.66 (m, 2H, H-1,9), 3.48–3.42 (m, 2H, H-4,6), 2.64 (s, 2H, H-10,11), 0.50 (s, 1H, H-5) ppm. 13C NMR (101 MHz, THF-d8, jb070.1.7) δ 163.60 (s, 2C, C-4a,5a), 139.03 (s, 2C, C-10,11), 138.27 (s, 2C, C-9a,11a), 132.65 (s, 2C, C-3,7), 132.05 (s, 2C, C-1,9), 120.67 (s, 2C, C-4,6), 112.44 (s, 2C, C-2,8), 83.67 (s, 1C, C-5) ppm. UV/Vis (THF): λmax 233 (ε: 1276(321) m2mol−1), 287 (ε: 2984(340) m2mol−1), 443 (ε: 631(102) m2mol−1), 513 (shoulder, ε: 411(65) m2mol−1) nm. ATR IR: λ−1: 2985 (w, –C–H st), 2926 (w, –C–H st), 1364 (s), 1068 (s), 912 (s), 724 (s), 436 (s) cm−1. Elemental Analysis for Litrop(dme)1.7: C (74.79%, calc.: 75.07%); H (7.78%, calc.: 7.95%). MP: 62 °C (decomp.).
Natrop: (5H-Dibenzo[a,d]cycloheptene-5-yl)-dimethyl-silane (1a, 2.005 g, 8.01 mmol, 1.0 equivalent) was dissolved in dry diethyl ether (30 mL). The resulting colorless solution was added to a white suspension of sodium tert-butoxide (0.769 g, 8.00 mmol, 1.0 equivalent) in dry diethyl ether (60 mL) over an ice bath. After 30 min, the reaction mixture was allowed to warm to a.T. and a dark red liquid was obtained. The solvent was removed under reduced pressure and dry 1,2-dimethoxyethane (30 mL) was added to the red residue. The liquid was filtered over a plug of celite, layered with dry n-hexane (80 mL) and stored in the freezer (−23°C, 2 days). The light yellow supernatant was discarded and the obtained dark green crystals were washed with dry n-hexane (2 × 10 mL) and briefly dried in vacuo (1.931 g, 6.16 mmol, yield: 77.0%; according to 1H NMR spectroscopy the compound contained 1.1 equivalents of dme).
1H NMR (300 MHz, THF-d8, jb075.3) δ 4.76 (ddd, 3JHH = 7.8 Hz, 3JHH = 7.1 Hz, 4JHH = 1.6 Hz, 2H, H-3,7), 4.08 (td, 3JHH = 7.1 Hz, 4JHH = 1.2 Hz, 2H, H-2,8), 3.68 (dd, 3JHH = 7.1 Hz, 4JHH = 1.6 Hz, 2H, H-1,9), 3.43 (d, 3JHH ≈ 6.9 Hz§, 2H, H-4,6), 2.60 (s, 2H, H-10,11), 0.56 (s, 1H, H-5) ppm. 1H NMR (400 MHz, C6D6/THF-d8, krastefa.50) δ 5.18 (td, 3JHH = 7.5 Hz, 4JHH = 1.6 Hz, 2H, H-3,7), 4.54 (td, 3JHH = 7.1 Hz, 4JHH = 1.3 Hz, 2H, H-2,8), 4.11 (dd, 3JHH = 7.1 Hz, 4JHH = 1.6 Hz, 2H, H-1,9), 3.93 (dd, 3JHH = 7.9 Hz, 3JHH = 1.4 Hz, 2H, H-4,6), 2.98 (s, 1H, H-10,11), 1.10 (s, 1H, H-5) ppm. 13C NMR (101 MHz, C6D6/THF-d8, krastefa.51) δ 161.95 (s, 2C, C-4a,5a), 138.79 (s, 2C, C-10,11), 136.39 (s, 2C, C-9a,11a), 133.16 (s, 2C, C-3,7), 132.57 (s, 2C, C-1,9), 120.12 (s, 2C, C-4,6), 113.22 (s, 2C, C-2,8), 81.56 (s, 1C, C-5) ppm. UV/Vis (THF): λmax 285 (ε: 3074(349) m2mol−1), 459 (ε: 803(158) m2mol−1) nm. ATR IR: λ−1: 3039 (w, =C–H st), 3003 (w, =C–H st), 2978 (w, –C–H st), 2932 (w, –C–H st), 2913 (w, –C–H st), 2869 (w, –C–H st), 2823 (w, –C–H st), 1553 (s), 1443 (s), 1362 (s), 1118 (s), 1082 (s), 1028 (s), 734 (s) cm−1. Elemental Analysis for Natrop(dme)1.1: C (74.20%, calc.: 74.36%); H (6.92%, calc.: 7.08%). MP: 45 °C (decomp.).
§ The upper part of the multiplet lies underneath the signal of the solvent DME.
Ktrop: Method A: (5H-Dibenzo[a,d]cyclo-hepten-5-yl)-dimethyl-silane (1a, 1.500 g, 5.99 mmol, 1.0 equivalent) and potassium tert-butoxide (0.693 g, 6.18 mmol, 1.0 equivalent) were placed under argon. Dry tetrahydrofuran (20 mL) was added and a dark red liquid was obtained immediately. The reaction mixture was stirred at a.T. (10 hr) and filtered over a plug of celite. The dark red filtrate was layered with dry n-hexane (68 mL) and stored in the freezer (−23 °C, 4 days). A first crop of red crystals was isolated (0.624 g, 2.34 mmol, yield: 39.1%; according to 1H NMR spectroscopy the compound contained 0.5 equivalent of THF). The supernatant was layered with dry n-hexane (60 mL), stored in the freezer (−23 °C, 3 days) and a second crop was obtained (0.461 g, 2.00 mmol, yield: 32.4%, overall yield: 71.5%).
Method B: (5H-Dibenzo[a,d]cycloheptene-5-yl)-trimethyl-silane (1b, 4.909 g, 18.57 mmol, 1.0 equivalent) and potassium tert-butoxide (2.085 g, 18.58 mmol, 1.0 equivalent) were placed under argon. Dry tetrahydrofuran (35 mL) was added over an ice bath. The yellow solution was allowed to warm to a.T. and a gradual color change to dark red was observed. The reaction mixture was stirred overnight. The solvent was removed under reduced pressure. The red residue was triturated with dry diethyl ether (2 × 20 mL) and then washed with dry diethyl ether (40 mL). The resulting red solid was briefly dried in vacuo (3.552 g, 15.42 mmol, yield: 83.1%). The red solid (0.271 g, 1.18 mmol) was recrystallized in dry tetrahydrofuran (5.0 mL), filtered over glass filter paper and celite, layered with dry n-hexane (10.0 mL) and stored in the freezer (−30 °C, 2.5 days). The long, crystalline needles were washed with dry n-hexane (4 × 1.5 mL) and dried under a stream of argon (0.171 g, 0.74 mmol, yield of recrystallization: 63%).
1H NMR (300 MHz, THF-d8, jb073.1.1EA) δ 4.47 (ddd, 3JHH = 7.9 Hz, 3JHH = 7.1 Hz, 4JHH = 1.6 Hz, 2H, H-3,7), 3.74 (td, 3JHH = 7.1 Hz, 4JHH = 1.2 Hz, 2H, H-2,8), 3.26 (dd, 3JHH = 7.1 Hz, 4JHH = 1.6 Hz, 2H, H-1,9), 2.97 (dd, 3JHH = 8.0 Hz, 4JHH = 1.3 Hz, 2H, H-4,6), 2.00 (s, 2H, H-10,11), 0.06 (s, 1H, H-5) ppm. 1H NMR (400 MHz, THF-d8, krastefa.11, T = 273 K) δ 4.40 (ddd, 3JHH = 8.2 Hz, 3JHH = 7.1 Hz, 4JHH = 1.6 Hz, 2H, H-3,7), 3.65 (td, 3JHH = 7.0 Hz, 4JHH = 1.3 Hz, 2H, H-2,8), 3.18 (dd, 3JHH = 7.1 Hz, 4JHH = 1.6 Hz, 2H, H-1,9), 2.89 (dd, 3JHH = 8.0 Hz, 4JHH = 1.3 Hz, 2H, H-4,6), 1.91 (s, 2H, H-11,10), −0.01 (s, 1H, H-5) ppm. 13C NMR (101 MHz, THF-d8, krastefa.12, T = 273 K) δ 162.96 (s, 2C, C-4a,5a), 139.26 (s, 2C, C-10,11), 138.42 (s, 2C, C-9a,11a), 133.95 (s, 2C, C-3,7), 132.89 (s, 2C, C-1,9), 120.17 (s, 2C, C-4,6), 111.87 (s, 2C, C-2,8), 89.44 (s, 1C, C-5) ppm. UV/Vis (THF): λmax 286 (ε: 3343(566) m2mol−1), 296 (shoulder, ε: 3086(595) m2mol−1), 478 (ε: 1025(277) m2mol−1) nm. ATR IR: λ−1: 3006 (w, =C–H st), 2985 (w, –C–H st), 2939 (w, –C–H st), 2924 (w, –C–H st), 1366 (m), 1121 (s), 1039 (m), 914 (m), 797 (m), 740 (s), 436 (m) cm−1. Elemental Analysis: C (78.25%, calc.: 78.21%); H (4.94%, calc.: 4.81%). MP: 240 °C (decomp.).
K2trop: Ktrop (0.461 g, 2.00 mmol, 1.0 equivalent) was dissolved in dry tetrahydrofuran (5.0 mL). The resulting dark red solution was added to a golden suspension of potassium graphite (0.355 g, 2.62 mmol, 1.3 equivalents) in dry tetrahydrofuran (5.0 mL) and stirred at a.T. (3 days). The dark red suspension was filtered over a plug of celite and the dark red filter cake was washed with dry tetrahydrofuran (3.5 mL). The dark red filtrate was split into two portions and each was layered with dry n-hexane (6.0 mL) and stored in the freezer (−30 °C, 3 days). The dark red, microcrystalline solid of both fractions was washed with dry n-hexane (2 × 2 mL each) and briefly dried in vacuo (0.372 g, 0.77 mmol, yield: 38.3%). The supernatant of both fractions was concentrated under reduced pressure and the dark residue was recrystallized again from dry tetrahydrofuran (3.0 mL) and dry n-hexane (6.0 mL) at −30 °C to give a second crop of dark red, microcrystalline solid (0.060 g, 0.12 mmol, yield: 6.2%, overall yield: 44.5%).
UV/Vis (THF): λmax 286 (ε: 4098(190) m2mol−1), 297 (shoulder, ε: 3857(204) m2mol−1), 361 (ε: 1988(237) m2mol−1), 482 (ε: 1633(37) m2mol−1) nm. ATR IR: λ−1: 3020 (w, =C–H st), 2970 (w, –C–H st), 2868 (w, –C–H st), 1324 (m), 1015 (m), 736 (m), 686 (m), 433 (m) cm−1. Elemental Analysis for K2trop(thf)(n-hexane)0.2: C (67.95%, calc.: 67.62%); H (5.92%, calc.: 6.12%). MP: >250 °C.
Na2dbcot: Dibenzo[a,e]cyclooctatetraene (0.507 g, 2.48 mmol, 1.0 equivalent) was dissolved in dry tetrahydrofuran (10 mL). The colorless solution was added to a Schlenk tube with a sodium mirror (0.55 g, 23.92 mmol, 9.6 equivalents). A swift color change to dark red was observed. The reaction mixture was stirred at a.T. (1 day). The solvent was removed under reduced pressure. The purple residue was suspended in dry tetrahydrofuran (7 mL) and filtered over a plug of celite to give a dark red filtrate (a) and a dark red filter cake (b). (a) The dark red filtrate was layered with dry n-hexane (10 mL) and stored at a.T. (7 days). The obtained dark crystals were washed with dry n-hexane (2 mL) and dried under a stream of argon (0.145 g, 0.34 mmol, yield: 13.6%). (b) The filter cake was extracted with dry 1,2-dimethoxyethane (6 mL). The dark red filtrate was layered with dry n-hexane (8 mL) and stored in the freezer (−30 °C, 6 days). The obtained dark crystals were washed with dry n-hexane (2 × 2 mL) and dried under a stream of argon (0.256 g, 0.45 mmol, yield: 18.3%, overall yield: 31.9%).
1H NMR (300 MHz, THF-d8, jb105.1.2) δ 7.87 (dd, 3JHH = 6.6 Hz, 4JHH = 3.3 Hz, 4H, H-1,4,7,10), 7.17 (s, 4H, H-5,6,11,12), 6.21 (dd, 3JHH = 6.6 Hz, 4JHH = 3.4 Hz, 4H, H-2,3,8,9) ppm. 13C NMR (75 MHz, THF-d8, jb105.1.2) δ 135.26 (s, 4C, C-1,4,7,10), 108.90 (s, 4C, C-2,3,8,9), 107.43 (s, 4C, C-4a,6a,10a,12a), 93.37 (s, 4C, C-5,6,11,12) ppm. UV/Vis (THF): λmax 238 (ε: 2523(2) m2mol−1), 261 (shoulder, ε: 1842(132) m2mol−1), 328 (ε: 5293(512) m2mol−1), 392 (ε: 853(87) m2mol−1), 514 (ε: 94(12) m2mol−1), 553 (ε: 106(13) m2mol−1), 597 (ε: 76(9) m2mol−1) nm.
K2dbcot: Dibenzo[a,e]cyclooctatetraene (0.301 g, 1.47 mmol, 1.0 equivalent) was dissolved in dry tetrahydrofuran (12 mL). Potassium graphite (0.526 g, 3.89 mmol, 2.6 equivalents) was added. The resulting dark red suspension was allowed to stir at a.T. (1 day). The reaction mixture was filtered over a plug of celite. The filter cake was washed with dry tetrahydrofuran (3 mL). The filtrate was split into two portions and each layered with dry n-hexane (8 mL) and stored in the freezer (−30 °C, 3 days). The obtained dark green crystals were washed with dry n-hexane (2 × 1 mL) and briefly dried in vacuo (0.450 g, 1.15 mmol, yield: 78.3%). The supernatant was concentrated under reduced pressure and the black residue was recrystallized in the same manner to give a second crop (0.047 g, 0.12 mmol, yield: 8.2%, overall yield: 86.6%).
1H NMR (300 MHz, THF-d8, jb085.1.1) δ 7.87 (dd, 3JHH = 6.7 Hz, 4JHH = 3.5 Hz, 4H, H-1,4,7,10), 7.17 (s, 4H, H-5,6,11,12), 6.19 (dd, 3JHH = 6.7 Hz, 4JHH = 3.3 Hz, 4H, H-2,3,8,9) ppm. 13C NMR (75 MHz, THF-d8, jb085.1.1) δ 135.72 (s, 4C, C-1,4,7,10), 109.36 (s, 4C, C-4a,6a,10a,12a), 108.91 (s, 4C, C-2,3,8,9), 95.78 (s, 4C, C-5,6,11,12) ppm. UV/Vis (THF): λmax 235 (ε: 3997(184) m2mol−1), 261 (shoulder, ε: 1053(87) m2mol−1), 326 (ε: 1959(338) m2mol−1), 388 (ε: 334(53) m2mol−1), 502 (ε: 38(6) m2mol−1), 544 (ε: 42(7) m2mol−1), 587 (ε: 31(5) m2mol−1) nm. MP: >250 °C.
[Rh(trop)(cod)]: Cyclooctadiene rhodium(I) chloride dimer (0.050 g, 0.10 mmol, 1.0 equivalent) and Ktrop (0.047 g, 0.20 mmol, 2.0 equivalents) were stirred in dry toluene (6 mL) at a.T. (12 hr). The dark red liquid was filtered over a plug of celite, layered with dry n-hexane (6 mL) and stored in the freezer (−30 °C, 13 days). The obtained dark red crystals were washed with dry n-hexane (0.5 mL) and dried under a stream of argon (0.052 g, 0.13 mmol, yield: 63.0%).
1H NMR (400 MHz, C6D6, jb083.8A) δ 7.01–6.88 (m, 6H, HAr), 6.85 (dd, 3JHH = 7.1 Hz, 1JHH = 1.7 Hz, 2H, H-4,6), 5.16 (d, 2JRhH = 1.2 Hz, 2H, H-10,11), 4.09 (sbr, 2H, CHCOD), 3.59 (sbr, 2H, CHCOD), 2.88 (s, 1H, H-5), 2.21 (sbr, 4H, CH2COD), 1.76 (sbr, 4H, CH2COD) ppm. 13C NMR (101 MHz, C6D6, jb083.8A) δ 137.43 (s, 2C, C-4a,5a), 132.63 (s, 2C, C-9a,11a), 128.06 (s, 2C, C-1,9/3,7§), 126.86 (s, 2C, C-4,6), 126.66 (s, 2C, C-3,7/1,9), 126.13 (s, 2C, C-2,8), 97.52 (d, 1JRhC = 5.4 Hz, 2C, C-10,11), 91.23 (s, 2C, CHCOD), 70.69 (s, 2C, CHCOD), 55.84 (d, 1JRhC = 13.2 Hz, 1C, C-5), 35.22 (s, 2C, CH2COD), 29.91 (s, 2C, CH2COD) ppm.
§ The peak is buried under the signal for C6D6.
1H NMR (500 MHz, THF-d8, jb083.8.2A, −40 °C) δ 7.10–6.99 (m, 6H, HAr), 6.89–6.84 (m, 2H, H-4,6), 5.46 (s, 2H, H-10,11), 3.92 (mbr, 2H, CHCOD), 3.70 (mbr, 2H, CHCOD), 2.81 (s, 1H, H-5), 2.30 (m, 4H, CH2COD), 1.76 (m, 4H, CH2COD) ppm. 13C NMR (126 MHz, THF-d8, jb083.8.2A, −40 °C) δ 137.75 (s, 2C, C-4a,5a), 133.25 (s, 2C, C-9a,11a), 128.54 (s, 2C, C-1,9/3,7), 127.42 (s, 2C, C-3,7/1,9), 127.24 (s, 2C, C-4,6), 126.78 (s, 2C, C-2,8), 97.57 (d, 1JRhC = 5.0 Hz, 2C, C-10,11), 90.61 (d, 1JRhC = 6.9 Hz, 2C, CHCOD), 70.35 (d, 1JRhC = 15.6 Hz, 2C, CHCOD), 56.45 (d, 1JRhC = 13.0 Hz, 1C, C-5), 35.09 (s, 2C, CH2COD), 30.46 (s, 2C, CH2COD) ppm.