110
H. Rudler et al. / Journal of Organometallic Chemistry 684 (2003) 105ꢀ112
/
C16H11NO5W, C, 39.94; H, 2.30; N, 2.91. Found: C,
1
39.29; H, 2.41; N, 3.01%. H-NMR (200 MHz, CDCl3)
d: 8.96 (d, 1H, Jꢂ
H-5), 8.30 (d, 1H Jꢂ
4 and H-10), 7.79 (dd, 1H, Jꢂ
(dd, 1H, Jꢂ7.4ꢀ7.4 Hz, H-9), 5.48 (q, 1H, Jꢂ
H-1), 2.53 (d, 3H, Jꢂ
6.4 Hz, H-2). 13C-NMR (50 MHz,
CDCl3) d: 202.0 (trans CO), 198.0 (cis CO), 138.7ꢀ
/
5.6 Hz, H-3), 8.58 (d, 1H, Jꢂ
8.1 Hz, H-7), 8.06ꢀ8.03 (m, 2H, H-
7.4ꢀ7.4 Hz, H-8), 7.67
6.4 Hz,
/
9.2 Hz,
/
/
/
/
/
/
/
/
/
120.2 (qC and arom CH), 50.1 (C-1), 32.4 (C-2).
idines, new tungsten ate complexes resulting from a
double reduction reaction. The formation and reactivity
of these complexes, which appears already herein, will
be taken into advantage to be extended to more
elaborate alkoxycarbene complexes.
4.3. Reaction of carbene complex 7 with dihydroquinoline
in the presence of pyridine: formation of complex 9
To a solution of 500 mg (1.09 mmol) of carbene
complex 7 (0.5 g;1.09 mmol) in diethylether (100 ml) at
r.t., was added by syringe dihydroquinoline 2 (0.15 g,
one equivalent). The reaction mixture was allowed to
stir for 15 min; then pyridine (0.09 g, one equivalent)
was added. After 15 h at r.t., the solvent was evaporated
under vacuum and the residue was chromatographed on
silica gel, giving a yellow solid (0.2 g, 0.4 mmol) in 37%
yield the spectroscopic data of which agreed with those
of complex 9.
4. Experimental
All reactions were performed under an inert atmo-
sphere of argon. The solvents were dried by distillation
over the following drying agents prior to use and were
transferred under argon: Et2O, THF (Na/benzophe-
none), CH2Cl2 (P4O10), toluene (Na). Chromatography
was carried out on Merck silica gel, 70ꢀ230 mesh. NMR
/
spectra were recorded on Bruker AC 200 or ARX 400
spectrometers; chemical shifts (d) are given in parts per
million relative to TMS and coupling constants (J) in
hertz. HRMS measurements were carried out on a
JEOL MS 700 instrument (70 eV). Melting points were
determined on a Reichert instrument.
4.4. Reaction of carbene complex 7 with dihydroquinoline
2 in presence of the enamine 12: formation of 14
To a solution of 500 mg (1 mmol) of carbene complex
7 (0.5 g, 1.09 mmol) in dichloromethane (50 ml) was
added dihydroquinoline 2 (0.52 g, 4 mmol) at r.t. After
total consumption of the starting material, 4-cyclohex-1-
enyl-morpholine (12) (0.608 g, 4 mmol) was added and
the reaction stirred for 15 h. After evaporation of the
solvent under vacuum followed by silica gel chromato-
graphy of the residue the adduct 14 was obtained as a
4.1. Preparation of dihydroquinoline 2
1,2-Dihydroquinoline was prepared from quinoline
and LiAlH4 according to the literature and isolated after
silica gel chromatography as a white solid in 95% yield.
white solid (121 mg, 0.468 mmol, 46.8%), m.p. 63ꢀ
/
65 8C
[20].
4.2. Reaction of complex 3 with dihydroquinoline 2:
formation of complex 4
To a solution of carbene complex 3 (0.8 g, 2.06 mmol)
in diethylether (50 ml), was added by syringe dihydro-
quinoline 2 (0.4 g, 1.1 equivalent) at room temperature
(r.t.) The reaction mixture was allowed to stir until
complete disappearance of the starting material (10ꢀ20
/
min). Flash chromatography on silica gel gave with
hexanes as eluent the starting carbene complex (0.32 g,
0.82 mmol, 40%) and with dichloromethane as the
eluent the ylide complex 4 in 44% yield (430 mg, 0.89
4.4.1. 4-(2-Benzyl-cyclohexyl)-morpholine
1H-NMR (400 MHz, CDCl3) d 7.29ꢀ
/
7.12 (m, 5H,
aromatic), 3.75 (t, 4H, Jꢂ
/
4.3 Hz, H-2 and H-6), 2.66 (t,
mmol) as a purple solid, m.p. 97ꢀ
/
99 8C. Anal. Calc. for
4H, Jꢂ4.3 Hz, H-3,5), 2.63 (s, 2H, H-13), 1.78ꢀ
/
/1.75 (m,