Ph.D. THESIS ABSTRACT SYNTHESIS, STEREOCHEMISTRY AND ...

Radu Gropeanu – PhD Thesis Abstract
some amounts of the starting materials were recovered. This was a sign that the temperature was
too low. However, the synthesis of 14 has afforded in good yield the desired triad.
N
1° 2 equiv. nBuLi/THF/-78°C
2° 2 equiv. B(OMe) 3 /THF/-78°C la t.c.
3° 2 equiv. pinacol
N
Br S
Br
65%
O
B S
B
O
4b O 11 O
Br
4b
N
S
7
1° 1 equiv. nBuLi/THF/-78°C
2° 1 equiv. B(OMe) 3 /THF/-78°C la t.c.
3° 1 equiv. pinacol
75%
1° 1 equiv. nBuLi/THF/-78°C
2° 1 equiv. B(OMe) 3 /THF/-78°C la t.c.
3° 1 equiv. pinacol
80%
Scheme 6
N
Br S
B
O
12 O
N
O
Br S
B
After the purification, only traces of the iodine-derivatives were isolated. The mass
spectra (FAB-MS) of 14 and 15 confirmed the assigned structures. The molecular peaks are
splitted; for example, for 14 (M = 1003) an usual distribution of M-2, M-1, M, M+1, M+2 peaks
characteristic to the dibrominated compounds occurred in the spectrum.
The 13 C-NMR spectra present characteristic peaks to the Csp2-Br at 114 ppm and no
signals corresponding to a Csp2-I bond.
Another dyad was synthesized in a different manner (Scheme 10), by an oxidative
coupling of two monolithiated phenothiazines.
N
2
Br S
Br
1b
1° 1 equiv. BuLi/-78°C/THF
2° dry CuCl 2
Br
Scheme 7
2.3. FERROCENO-PHENOTHIAZINE MACROCYCLES
Ferrocene represents an interesting redox-active material and, recently, the ferrocene core
has been used as a building-block in the construction of redox-active and responsive
macrocycles. 41
Thus, the prospect of integrating strongly coupled redox fragments like phenothiazines
and ferrocenes into conjugated chains could constitute a so far unknown class of redox
addressable molecular wires. In particular, the integration of these synthons into a fullyconjugated
macrocycle represented one of our main goals.
Palladium-catalyzed cross-coupling reaction were described to be an effective method in
the synthesis of ring-substituted ferrocenes. 42 From these methods, the Suzuki and the Negishi
41 a) Dinnebier, R.E.; Ding, L.; Ma, K.; Neumann, M.A.; Tanpipat, N.; Leusen, F.J.J.; Stephens, P.W.; Wagner, M.
Organometallics 2001, 20 (26), 5642, 5647; b) Beer, P.D.; Crowe, D.B.; Ogden, M.I.; Drew, M.G.B.; Main, B. J.
Chem. Soc., Dalton Trans.: Inorg. Chem. 1993, (14), 2107-2116; c)Beer, P.D.; Nation, J.E.; Brown, S.L. J.
Organomet. Chem. 1989, 377 (1), C23-C26; d) Bell, A.P.; Hall, D. J. Chem. Soc., Chem. Commun. 1980, (4), 163-
165; e) Plenio, H.; Aberle, C. Chem. Eur. J. 2001, 7(20), 4438-4446; f) Plenio, E.; Aberle, C.; Al Shihadeh, Y.;
Lloris, J.M.; Martinez-Manez, J.; Pardo, T.; Soto, J. Chem. Eur. J. 2001, 7(13), 2848-2861.
S
N
13
16
N
S
O
Br
20