by recrystallization from cyclohexane-diethyl ether, to give the title
compound rac-8 (0.37 g, 0.8 mmol, 56%) as colourless crystals, mp
99 ◦C. 1H NMR (500 MHz, CDCl3) d 7.45 (d, J = 7.3, 2H), 7.41–
7.30 (10H), 6.98 (d, J = 8.6, 2H), 6.81 (d, J = 8.6, 1H), 6.76 (d,
J = 8.6, 1H), 6.03 (ddm, J = 5.0, 10.2, 1H), 5.96 (dm, J = 10.2,
1H), 5.25 (s(br), 1H), 5.09 (s, 2H), 4.99 (s, 2H), 3.49 (m, 1H), 2.64
(ddd, J = 4.7, 8.6, 13.7, 1H), 2.44 (ddd, J = 8.2, 8.2, 13.8, 1H),
2.07 (ddm, J = 9.6, 17.5, 1H), 1.97 (ddd, J = 4.0, 4.0, 17.6, 1H),
1.82 (dddd, J = 5.0, 8.7, 8.7, 13.8, 1H), 1.62 (dddd, J = 3.6, 8.7,
8.7, 13.3, 1H); 13C NMR (125 MHz, CDCl3) d 158.5, 156.8, 137.2,
137.0, 134.5, 133.6, 129.8, 129.4, 128.6, 128.5, 128.0, 127.8, 127.6,
127.5, 127.4, 125.9, 114.5, 114.5, 73.8, 70.1, 70.0, 65.8, 37.6, 31.2,
30.6; IR (KBr-disc) n/cm-1 3433 (w), 3033 (w), 2910 (w), 2887 (m),
2856 (w), 1610 (m), 1582 (w), 1510 (s), 1454 (m), 1383 (m), 1297
(w), 1238 (s), 1174 (s), 1112 (w), 1081 (m), 1066 (m), 1045 (m);
LRMS (FAB) m/z 476 ([M +H]+, 13%), 197 (11%), 136 (65%),
91 (55%); HRMS (FAB) calc. for C33H32O3 (M)+ 476.2351. Found
476.2381; Anal. calcd. for C33H32O3: C, 83.2%; H, 6.8%. Found C,
83.0%; H, 6.6%.
(M+H)+ 299.1647. Found 299.1629; Anal. calcd. for C19H22O3: C,
76.5%; H, 7.4%. Found C, 75.9%; H 7.4%.
Acknowledgements
This work was performed in the course of a research and devel-
opment project with the Zylum-Beteiligungsgesellschaft mbH &
Co. Patente II KG, Scho¨nefeld (Germany), in cooperation with the
IP-Bewertungs AG, Hamburg (Germany). Financial support from
the former institution is gratefully acknowledged. The Zylum-
Beteiligungsgesellschaft mbH & Co. Patente II KG owns the
international patent.57
Notes and references
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+
Found 299.1658; Anal. calcd. for C19H22O3: C, 76.5%; H, 7.4%.
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◦
1
(II) (38 mg, 0.12 mmol, 95%), mp 162 C. H NMR (300 MHz,
CD3OD) d 7.19 (d, J = 8.4, 2H), 6.99 (d, J = 8.5, 2H), 6.76 (d, J =
8.6, 2H), 6.68 (d, J = 8.5, 2H), 4.23 (dd, J = 1.8, 10.9, 1H), 3.43
(m, 1H), 2.70–2.51 (2H), 1.94–1.46 (8H), 1.27 (1H); 13C-NMR
(75 MHz, CD3OD) d 157.8, 156.4, 135.8, 134.6, 130.5, 128.7,
116.2, 116.0, 81.2, 79.0, 39.8, 34.4, 32.6, 31.9, 25.2; IR (KBr-disc)
n/cm-1 3324 (m), 2935 (m), 2858 (m), 2360 (w), 1614 (m), 1514
(s), 1445 (m), 1228 (s), 1072 (m), 1025 (m); LRMS (ESI) m/z 187
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+
(50%), 281 (40%), 299 (100%); HRMS (ESI) calc. for C19H23O3
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